I had a needle go in my mouth at least 5 times today. I had to get my cavaties fixed, so he gave the shot to numb my mouth. Honestly, they can hurt. It really depends. Usually for me, the shots on the arm don't hurt a bit. I remember one time, the lady said "alright, all done" and I didn't know she put the needle in already. But today, I teared up a bit at the 4th shot in my mouth, while the rest of them didn't hurt. Just make sure you don't look at them putting it in. It's best to think of something else.