bad knees! need advice!

Might also try glucosamine chondroitin. I've been taking that triple strength OTC supplement for about 10 yrs. It can take up to 3 weeks for the stuff to do its thing, but taken daily, all your joints will have greater flexibility and lubrication.
There are brand names that cost a bundle, but I just use the store brands.

I've had a serious knee injury and went through a total of 3 yrs. physical therapy, practically learning how to walk again. I have atrophy in my quadricep so lunges and step ups are difficult for me as my other leg compensates for the weakness of the other.

Take your time and stretch your legs really good (good to do this several times a day as well)

Before your workout, do a 10 min. bike warm up (prepares your joints for a workout)

Post workout, stretch really good again, then ice and elevate for 15-20min.

Ice & elevate 3x a day.

You can get a foam roller and do more stretching on that. I get a good stretch for my ITBs on my foam roller, I use it every day.

I also stopped eating gluten (whole wheat) and I am virtually pain free, no arthritis and no swelling - even from long walks etc. Glucosamine & chondroitin might help you as well. While you wait to see a specialist I'd try doing these things, but you really need to get a doctor's opinion.

ETA: focus on no impact, you can do plenty of exercises that do not require any impact. Good luck

I am also really hitting my stride with my new healthy routine and have run into knee troubles. Mine aren't as hindering as yours sound like, but I have been trying a lot of different things to push through. I think that good shoes are a must. I think any well known brand should be good...look for running shoes because they are lighter weight and good shock absorption. I have been a purchaser of Ryka athletic shoes exclusively for at least 10 years. They are made for women only and I can tell.

I agree with some of the other pals...the doc needs to be your final call on whether or not there is an injury or medical condition. Aside from that, staying away from all refined flours and sugars will reduce joint pain throughout your body. No white breads, rices, pastas and of course white sugar. These things are so processed that your body doesn't know how to break them down and after trying all the ways it can to use them, they get stored in your joints until they are absorbed or released and that takes a lot of time. I ate a white bun one day and the next my knees felt like I had struck them with a ball bat! Also omega 3-6-9 oils help, but you must consume them in rather large quantities and for a long time before you really notice.

On days when my knees just don't seem up to a workout, I get my heart rate up with shadow boxing...sometimes in a deep squat if I can muster it with forward punches and then punches out to the side etc. Then I do planks, push-ups, crunches and such without taking much break between to keep my heart going.

Hope this helps! Good Luck!