Tried doggy for the first time yesterday and it hurt so bad. Normally when I have sex, the first few pumps hurt but then I open up, literally and it starts to feel better. Well we were having sex in the missionary position then changed to doggy and it hurt so bad when it first went in, unlike missionary or riding. As he was literally pounding me (what I like but it hurts me doggy) I felt a pain in my right side where I would get cramps. Why does doggy hurt so much?