One time, I was on my way to the hospital to get an operation done. Nothing serious at all, but I was way nervous and hadn't smoked in like a week. I was riding with my old man, and he pulled out a spliff in hopes it would calm my nerves before we got there. Well we smoked this dube, and we stopped at the gas station. I didn't feel quite right, so I went in while he was pumping gas to use the restroom. I walked through the store to the bathroom, and when I got there I decided I was gonna pass out or something. I walked to the cooler instead, and grabbed a sprite. I walked up to the counter and sat my soda down, waiting for James to get done pumping the gas. I knew I was going down, because I'm practically holding myself up with the counter. I tell the clerk I'm leaving my soda there, and going to my car, that my husband will pay for it when he comes in. I turn around and take about 3 steps to the door, and I went down! And down hard! I took out a whole mother fucking beef jerky rack. The next thing I know, I'm laying on the floor with the clerk smacking the shit out of my face. Needless to say, she wouldn't let me leave until after an ambulance came. After I came to though, I felt just fine. This has also happened to me a couple other times, but not in public.
I think maybe it's lack of oxygen?
Just be thankful it didn't happen to you in the middle of a gas station.