Help Exercise is bringing me down

If you're not losing weight, you're not on a calorie deficit.

That's as certain as if there's no gas in my car I can't drive it. Just a fact of nature. What that means is if you want to lose weight, track your calories, and it becomes simple. If you're already doing this, your numbers are off, find out where.

You didn't tell us what kind of feel bad, so it's not possible to give decent advice. Sore, tired, depressed, they're all "bad" and mean different things.

With regard to the scale ‘not moving’ it’s unlikely that the workout you describe would burn many calories, obviously it completely depends on your height and weight, but for me, I’d maybe burn 300cal doing this routine I expect. So doing this session 3 x per week it would take me about 12weeks before I lost a single pound! And that assumes that I don’t have any extra calories as a result of being more hungry or taking a drink to the gym that has calories in it.

Now granted you may be significantly heavier/taller/male and thus have a somewhat greater calorie burn but essentially my point is that it would take a long time to see the scales drop from what is essentially not a massive calorie burning level of activity. Do not get me wrong, it is absolutely SUPER that you’ve increased your activity level and I’m sure you’ll see fitness gains almost immediately, so when you do, keep pushing yourself out of your comfort zone - to add another 5 minutes on the rower or put some jog intervals into the walk or increase the time you spend on each machine by 10% etc.

Just be patient - it’s much easier to reduce the calories that you eat than it is to burn them off hence many people you’ll hear saying that weight loss is ‘80% diet / 20% exercise’

Your body does not need to be “shocked” unless you are in cardiac arrest.

At the beginning of a new workout plan, you will likely retain water as part of the normal muscle repair process. This could explain why the scale has not gone down.

Doing an hour of exercise 3-4 times per week may be too much for your body at this time. Try doing shorter workouts and gradually increasing the time.

We would need to know your current weight, goal weight, and height to make any suggestions about your calorie intake. It’s okay to eat different amounts on different days as long as you are in a calorie deficit for the week.. If you follow your MFP calorie goal consistently, you will be in a calorie deficit. However, if you aren’t weighing all solid food with a food scale, then you don’t know how many calories you’re eating.

It is perfectly normal to feel tired the rest of the day when you are first started an hour of cardio.
It is going to take your body some time to increase your mitochondria. Once it does that, your overall energy will increase.
Give it a few more weeks. I agree that you are probably retaining water because you are building muscle. I returned to the gym in March after a six month absence. I was sore and tired for over a month. Now I feel fantastic.