Hello Dear, good that you are seeking a help. I can understand your suitation. From your brief, it looks like you are not able to clearly define your problem. But sure you are not the same girl 2 years back and something is bothering you. . There may be many reasons for this change due to studies, pressure about exams, peer pressure, friends, some lose in the family etc. It's always good to seek help when you are in trouble. Suggest you to keep your parents informed about your state of mind. You may just need a guidance to handle the suitation through a counseling session. Follow their advice and you should be able to overcome soon. God bless you.
Next Steps
Inform your parents about the problem and go for a counseling session immediately.