Is it normal i passed out like this once

Once in school when I was like 10 I got a very sharp back pain from nowhere and I was just going to tell my teacher about it when I passed out from nowhere. I woke up to lying in my teachers lap and she was drying food from my face because this happened at lunch. -_-
I have always wondered what caused this. No one took me to any doctor. I got sent home and I went to rest. I just got a very similar pain in the middle of my back and it reminded me of that. I just hope I dont suddenly pass out this time but probably not though.