I'm sorry you're in so much pain, that sucks. I think the others have given you good advice, I just have one other idea if you are going to work on strengthening your knees. You can do really easy exercises to build up those muscles with one of those tube things with the handles on the end. You can put one end around something stable and then put your foot through the other handle. Then you can move your leg away against the band.. you can go to the side, to the back/front and then cross it over your other leg to work the other muscles... I think I did a terrible job explaining that, does that make sense?? I will look and see if I can find a website or something that is more clear..
I also think swimming would be a really, really good idea if you have any way to access a pool!
Good luck! --Steph
-------------------- ~~I'm not crazy, I'm just a little unwell-I know right now you can't tell~~Matchbox 20
IBS-D,pain.