Im sorry to hear that youre not feeling well. I think you should h**e a rest. Maybe you should see a doctor. Dont be too tired and stressed out. Its bad for your health. If you get stressed out or tired, you can listen to some Chinese songs. I think its good for your Putonghua. And you can make some Chinese friends. Chinese people are friendly. You should find a right way to learn Putonghua. I think your Putonghua will be better one day.