What do you people think please?

Hey, im 20 but i figured this section was as good as any since this started when i was 18. I don't believe im epileptic, but my friends made me do some research. At least 5 times now while hanging out and smoking marijuana, i'd take a large hit, exhale and feel incredibly light headed. I'd get tunnel vision, and eventually lose control, fall over and blackout followed by convulsions. This has happened while sitting in a chair, falling out of a chair and falling down a few stairs, so its not exactly been comfortable. I'd normally just look at this and say ive been smoking too much, but the other day we took magic mushrooms, and i saw something really disturbing on TV (the movie Emily Rose, where they first show her convulsing). i felt sick and got the spins and before i knew it my friends said id blacked out in my chair, dropping the bong which i had only been holding and then my arms and legs were tensed and jerking violently with my eyes rolled back, scary thing was that i was pretty much aware of this the entire time. These feelings pass after about a minute, and afterwards i feel completely clearheaded and only discomfort i have is usually in my leg cause ive stretched it out so much. So far things that ive read that ive noticed in me are that i can feel them coming on and i've learned to take deep breathes to let the tunnel vision pass, and many times just as im starting to fall asleep at night i have muscle twitches in my leg. This would be something id easily visit my doctor about, except for the awkward fact that i have to say it only has happened during drug use. I'm willing to admit that to them, but id like to first be sure that this is a possibility. For all i know i could just be a dumbass who smokes too much pot. Thank you, Rich.