Dear Lily,
I'm sorry to hear that you feel tired and nervous,because you study too much time .Also, there are some pimples on your face. I think I can give you some advice.
First, you'd better stop to have a good rest, or you'll be too tired to study well. You should sleep at least eight hours a day. In addition, maybe you can finish homework at school and you can relax yourself when you get back to home. Listening to music is a good way. Also, if I were you ,I would eat more vegetables and fruit. They are good for your health. Don't you think so ? What's more, why not do sports after class? It can not only make you stronger ,but make your brain have a rest.
I think you can take my suggestions and feel better soon.
Yours,
Meng