I am able to understand how u must b feeling.  Not having a good relationship with a person u like can cause a lot of stress. But when the stress is lot to the extent of causing depression and anxiety it needs to be treated. Depression makes a person lose his confidence, motivation, interest reduces his concentration and potential. Anxiety causes bodily symptoms like palpitations sweating and tremors. V would need to know a few more details like ur sleep, appetite other situations that might make u anxious etc to give appropriate suggestions. Ur problem can be easily treated with counselling and if needed medications. U will be able to function better with it. Its not ur fault. It usually occurs because of chemical and hormonal changes in the  brain. Don't let ur problems affect ur personal or professional help. U need to consult a psychiatrist. U can also consult me online through the Practo chat option. Best wishes for speedy recovery!!

Fix daily schedule with activities of your liking, if possible play outdoor sports, go out with friends.