Dear Sally,
i'm sorry to hearthat you're not feeling well,i think you should have a rest.You'd better not go to school if you are too tird.You may feel relaxed if you listen to quiet music or go outing with your friends.It may help you a lot just to have a talk with your family.As for Putonghua ,I think you should't be shy.Try to talk as much as possible.Don't be afraid of maling mistakes.Liatening to the Chinses radio program is also a good way to improve Putonghua.Cheer up.You'll be better soon.
Yours,
(xxx)