That sucks a lot. I know for stomachaches, don’t do anything, and just lay down. I know that because I’ve had a lot of stomachaches before. (I eat too much)
As for other advice, just drink a lot of water and most importantly, get well soon!
hEy yOu bOLD mY sToLe fOnT
I can use it though. (Hey, you stole my bold font!)