It depends how close you are to the shooter, and how skinny/ big you are (no offense). You should never, ever, shoot each other close range on purpose, I knew a girl who did that and she got welts so infected she had to have them drained at the hospital. It also depends on what you are wearing. Wear something thick, but not too heavy as you will get hot and tired. But don't wear short sleeves because that will hurt haha.
Paintball hurts. Wear three or four layers of clothes, a toque might help, and the paintball place may supply coveralls. Don't wear good clothes. The paint can damage them. It's lots of fun, but make sure that you are well padded!
I've been paintballing, it wasn't too bad, but I guess it depends on your pain tolerance as well, I was only wearing my regular clothes and come coveralls. Just don't shoot each other when you're too close to one another.
I kinda have a feeling that anybody who gets hit with a paintball gun is going to get hurt! But I guess it depends on what your wearing and how hard it hits you? I don't know
paintballing dosnt hurt alot. just a 5 second sting.