I agree with Darkeyes. It's rather easy to read through your post and say, "Well that sounds like a bipolar symptom, that one doesn't," etc. but I really think it would be best to see a doctor. It might help to take a copy of your post with you.

I further agree that effective treatment is very possible. You don't have to continue to fight this battle on your own.

One thing no one else has pointed out, and forgive me if I overstep here, but regarding the children you babysit, if you truly believe you may one day lose control, I think you should cease to take them in until you get some help from a doctor.

I wish you all the best of luck. Take care.