Changing Calorie Deficit Stalled Weight loss?

"I just wanted to post something about what to expect during the phases of weight loss.

Overview (why I'm posting this)
Over the course of about 7 months on here, I have seen many people succeed, I have also seen some drop off the map. I expect this is because some succumb to the demon that is temptation, and some to the devil that is disappointing. I wanted to give a few "heads up"s to both new comers and veterans to the site. Some may know already, some may not. But either way, if this helps anyone to set more realistic goals in their own head, I feel like it has done it's job.

Phase 1. The start of a brand new day! (or week, or month, or year)
Expectations are sky high, usually so is motivation and intentions. This is where most people lose the most weight. At the start it's not uncommon to see 4 to 8 lb losses per week. The reasons for this are mostly (sorry to disappoint) water weight. You drop excess water quickly, and you can have up to 5 lbs of water weight. The next biggest reason is the fat that is right next to the blood vessels, the stuff that you put on in the last month or three, it will melt like butter usually.

Phase 2. Reality setting in.
At about week 3 to a month or so, people suddenly realize that they are no longer dropping 8, 6, or even 4 lbs a week. This is a crucial phase in your journey. Expect this, it is natural. You have shocked your body by changing both eating habits and exercise routine. Now it has had a little while to become used to the new lifestyle, it's going to compensate. Your body still doesn't believe it's permanent yet, so it will still try to store some fat, so now that it knows how to regulate it's new metabolic levels, it tries to store fat in earnest. It's not uncommon for people to hit a wall here, no loss for weeks. Expect this as well.

Phase 3. The routine.
At about 2 months or so, your routine is pretty much set, your body is beginning to believe that you really want to STAY the way you are going now. You will start to see more consistent (but lower, usually 1 to 2 lbs a week) loss, also, you should start seeing some muscle tone (depending on how much you had to lose in the first place). If you stop to think, you should realize that you have improved dramatically in your exercise levels. If you do cardio, you should notice how much longer and harder you can work. This is important to realize as it is just as big of an indicator as weight loss. Also, by now you may notice that your clothes no longer fit right. This is also very important. The weight may not be falling off anymore, but you are becoming a smaller person. Weight is arbitrary, if you are building muscle (which your body is doing at a furious pace by now) you won't notice huge losses, but you will notice wholesale changes in the mirror!

Phase 4. Really digging in.
This is where the second wall can happen. You're probably at between 3 and 4 months by now, and if you have gone this far, you feel like you have already succeeded. This is where many people stumble. they are tired of the routine, tired of eating different things from all their friends, limiting their alcohol intake. Basically the shine has worn off. this is when your really need to plant your feet. Maybe change up your exercise routine, make a concentrated effort to find different, but still nutritional food. Talk to people. And examine how far you have come. At this point, no matter how much external motivation you receive, it's all about believing in yourself!

Phase 5. End game.
5 or 6 months in you are probably working on that "last 10 pounds". This can be discouraging for many as it is a slow burn. Remember, your body probably feels like it is where it needs to be, your brain might think you need to lose 10 more, but your body is quite proud of itself now, it feels like it has "Done enough" and it wants to stay RIGHT HERE. The body LIKES to have a little fat around just in case, especially for the ladies (sorry girls, it's just human physiology). If you feel like you still need to lose it, prepare yourself for some guerrila warfare against your body. Design an exercise regimen that is very dynamic, forget the "same thing every day". Make a plan that challenges you both physically and mentally. Make sure you give yourself a day off here and there to just veg. And by all means, remember, muscle burns fat at rest. So get some weight or resistance training involved.
The last 10 may take 3 to 6 months to lose. I know nobody wants to hear that, but it's true. And forget the idea of increasing your calorie deficit, healthy bodies need good nutrition, your body no longer has the fat reserves to handle the large deficits you could when you were 30 40 or 50 pounds overweight. Better to make it a 3 or 400 calorie deficit (NET, please count your exercise calories too!). It may take a bit longer, but your body will like you for it. Plus it feeds those new muscles and keeps them burning fat, keeps your skin healthy (elasticity is important when you want those places that were stretched out to "snap back") and keeps you from getting head aches and depressed.

Conclusion:

This is what I have learned, not just from my journey, but from others as well on here. It saddens me sometimes to see people hit one of these stages and not recognize it for what it is, a part of the process. If we all can have realistic expectations, then we are more prone to win the fight and stay healthy in the long run. Note that some people will hit these stages harder then others, some may take longer, but for the most part, this is the rule that the exceptions will come from."

Based on my experiences, JaneDough nailed it. One small difference was that for me, I took the "if it ain't broke dont fix it approach" when it came to my exercising instead of changing it up as she mentioned in Phase 5. Everyone is different and you'll need to find what works for you.

Realistic expectations and time duration is a must, none of this will happen over night. To address your original question... double check your numbers for TDEE, and double check the numbers (via a food scale) that you are putting in for your food. Choose a deficit that will work for you (a 500 cal a day = 1lb a week deficit is a very safe healthy way to go about this). This will likely mean eating back your work out calories. Once you figure out numbers that work for you, try to stay consistent. It's a long road.

Consistency and sustainability is perhaps the biggest pitfall I've seen.