What is happening to me?

Hello everyone, Recent events have motivated me to research seizures and eventually end up here. I think I may have epilepsy. Within the last 2 years I believe I have had 5 seizures. The first one was last year in my english class. I was sitting upright in my chair and started to feel very weak, tired, numb. Eventually my vision blurred and I woke up on the floor after falling out of my seat. I was told I passed out because of sleep deprivation, but I do not think that is the case. The next three have happened while I was urinating after drinking a couple of beers. It felt exactly like the first time. One of these times I had just rolled out of bed late at night and went straight to the bathroom. Finally, the other day after recreationally using marijuana, I started to feel these symptoms arise once more. I was sitting down and I could feel something was wrong. I got up and started to walk towards the bathroom hoping I could just walk it off. A moment later I woke up with my back to the floor, dazed and confused. A friend speculated I was "convulsing a little." Everytime after one of these seizure events I wake up very confused, but I regain full control after a few seconds pass. I am extremely frightened to think what the hell is wrong is me. 4/5 times I had been under the influence of something, and 3/5 I had actively been urinating. The obvious answer for now is to quit all drug use and see a doctor. My job requires me to be in peak physical health and I am sincerely terrified to hear what the doctor diagnoses me with. Does anyone think they know what I have? What should I do? Thank you all, -C130