Well I had this one baby ball python who bit me. Took the skin clean off my finger and it wouldn't stop bleeding for an hour. There was blood everywhere!

Ok, not really. I've been bitten by a couple ball pythons. One was a hatchling and I can honestly say I couldn't feel it. I saw a small dot of blood and that's the only thing that convinced me that I actually got bit. Baby ball pythons don't hurt at all. When they get larger, it feels like a tiny pin prick but that's it.