sounds like a mild form of PTSD... if the dose of pot you took was so hight, and you had a panic attack that was really bad and scary, your mind will remember that, and you'll feel high... used to happen to me the first few times I smoked, before I knew my limits. Smoke a cigarette to calm down (it helped me), but I'd definately smoke a small amount of pot, and enjoy the high. That way, when your mind thinks of marijuana, it will remember the most recent good experience, than the bad one.
Good luck, and I hope you get better.