How are you getting on? I have learnt about your bad mood from Peter. I truly feel sorry for you.
It is easy to see why you are so upset. I know that your mother always nags at you. But she is just concerned about you. If you think your mother is always finding fault with you, you should sit down and discuss the problem with her. The longer you remain silent, the worst it is going to become. Sometimes, it is best to get things out in the open before they get any worse.
It is important that we should appreciate the efforts of our parents. So, you must try to talk more to them. Let your mother explain to you the reasons behind her actions. But of course, there must be some differences in your perspectives. While you may see yourself as a grown-up and can make your own decisions, in your parents’ eyes, you are always their little daughter.
On the other hand, you must show your parents that you can take care of yourself. Besides, you may want to talk about your problem with your father and sister, who can give great support.
To conclude, if I were you, I would be less pessimistic about everything. At present, I think you may find it helpful to pull yourself together and study hard. When you can get good results in examinations, not only you, but also your parents will be very pleased.