It's called Stevens-Johnson Syndrome, but while that is the most well know rash associated with Lamictal, there are many other rashes that occur with the medication, all mild, so I wouldn't panic. If you google it I'm sure you'll come up with a dozen gory pictures but I think I'd call my doctor or pharmacist. I got hives with lamictal and had to discontinue. It was no big deal. Usually with a rash they have you discontinue the med because theres no way to tell which rash will progress to SJS.
Good judgement comes from experience and alot of that comes from bad judgement.
You just have to accept that some days you're the pigeon, and some days you're the statue.