I've recently started experimenting with marijuana...?

and it's starting to make me think I'm clinically depressed. typically, I'm a very very pessimistic person and just generally don't feel very good about myself or anything, but whenever I smoke I just feel good/relax/happy even days after the high has left me. so my question is could marijuana be having antidepressant effects for me or is this just what marijuana always does for everyone?