Lost of confidence and enthusiasm. Me.

I am studying as well as working as a freelancer. I am in my final year already it's too late. It happened during exams. After studying so much i wasn't able to write paper because I forgot everything. It happened fir almost all papers. Since then I lost confidence in everything. I tried to overcome by seeing positive and surround myself with positive people but its not helping me. It is affecting my work life as well as my student life. My mind tells me I'm finished. I can't be successful in life. You r not that person anymore that you used to be. Now the situation is I'm fearing of everything like giving exam doing work meeting new people. Suddenly the light inside of me died and it's consuming me. I did 12th in 2007 and after that I wasted two yrs of my life and then due to financial problem I got stuck in engg for almost 6 years. I left that and now doing bca. I think I'm still stuck in the past and don't know the way to get past that. Please help me.