It sounds like this is something worth discussing with a counselor, star. When something is happening inside you that you have no control over, it can be scary. But you seem to recognize some sort of pattern here, you recognize it when it happens, you have that on your side. No one here can diagnose you, that's up to a trained professional. But I can tell you that something similar used to happen to me (still does, though rarely now) and I was medicated at that point for anxiety. I'm sure this sounds familiar to a lot of us. Don't be afraid to see a counsellor, or talk to your doctor about this.
Keep posting!