For about a year now I will just start crying at random times and have no idea why. It doesn't happen often but when it does its persistent for a week or two. I am an 18 year old girl, and for the most part am very happy. I have been through a few rough times though, but I don't think I have depression. After I have one of these crying attacks I get very tense and shakey and find it difficult to breath. I usually get a sudden feeling of anger before this happens also. Any ideas on what is going on with me?

It sounds like some kind of panic attack. Have you talked with your doctor or a counselor about this?