Dear Sally,
I’m sorry to hear that you're not feeling well.I think you should go to bed eraly.And you shouldn't study to late.You should drink some water,it helps to your health.I think you can talk with your Chinese friends.This can help you improve putonghua.You shouldn't stresssd out,you should listen to some music.
I hope you feel better soon!
自己写的,可能有些错误,