Hi DancingTUMMYProblems<3
and welcome to the forum!
I'm sorry to hear about your diagnosis and everything that you've been going through. Although I'm very happy that you seem to have a wonderful support system.
I was diagnosed when I was 9 during summer break before 5th grade. I also had a hard time with school due to being sick a lot. Best thing to do is to talk to your teacher and let them know how you're feeling. Your parents/guardians will handle the rest of the school stuff to make sure that you don't fall behind. I remember my teacher let me sit in the back near the door so I could slip out and use the bathroom without asking. If you think you need that then ask your teacher about it (or have someone else talk to them for you if you don't want to).
Make sure you get plenty of rest and don't overdo it on the playground. Its not uncommon to feel weak sometimes so if you do then sit down for a while. You can also get out of PE if you need to. I sat out sometimes but a lot of times I'd just get up and run with the rest of the class as I had bursts of energy here and there.
What kind of dance do you do (I'm assuming ballet by your avatar but do you do other kinds or is that your favorite?)? I never got to do dance classes but I did take some karate classes in 5th grade. I also draw.
Would love to see some of your art work some time and if you want you can see mine too.
Keep us posted on how you're doing.