hi. i am 13 years old and i think i know how to masterbate. i tried it, but i don't know what is supposed to happen. are u supposed to feel something around ur hips? like something sucking on it (inside)? i feel that, but i never been able to actually "come".... i'm always forced to stop because it kinda hurts (only done it like 3 times) and i always have to somehow piss after i "masterbate". but when i piss, i see blood. is this normal? if not, how can i fix it? am i doing anything wrong?
EDIT: i'm a boy
