Out of no where nothing makes me happy, im never depressed but now it just doesn't go away.i feel terrible & it affects my family. i'm on birth control?

Consider stress: Analysis. Seek friends to talk to and look for life stress events being overwhelming. Moving, marriage, new job etc . May build up and be hard to handle. If needed, seek professional counseling. If religious, consider talking about your values with minister, rabbi, clergy. Maybe find a group of people similar to you and join them or blog.

Seek medical help: For this , as yet, unexplained change in your mood.If you have a good family doctor, you can start there.