Major muscle fatigue

I was recently diagnosed with crohns disase in november and my doctor put me on pentasa. It helped with some symptoms but lately ive been experiencing horrible fatigue. I am a dancer and I take 13 dance classes a week. I usually have multiple classes in one night and lately my muscles have been giving out on me and i can barely make it through my classes and Im becoming too week to do a lot of things in class. This is really frustrating for me because dance means a lot to me. I am going to college for dance in the fall and I will be dancing even more then I am now. Does anybody have any advice on how to help this?? I just want to get back to my old self again.

.....for me it's potassium...i don't absorb it..that needs to be checked often too! Good Luck