I was driving down a four lane road in the rain a few months ago when a migraine started. I was in the middle lane when shooting pain started above my left eye. The lines in the road started weaving and became thick, the lights on the cars became distorted, and my vision became very distorted. I took a triptan (Zomig sublingual) and it went away quickly.
As Ann recommended, I went to the doctor because it was a new headache I hadn't experienced before. He confirmed it was just an aura and a migraine.
My neurologist and doctor have always recommended that if my headaches change that I should check in with them. They have always confirmed it's just a different form of a migraine, but it puts my mind at ease because some of the symptoms are rather disconcerting.