... why does this always happen?

Why does it hurt me still so much? I had with my boyfriend about 3 weeks ago for the first time, every weekend we've had ... lots of it... Still it hurts me, sometimes i bleed a little not a lot but a little, like it's basically a small drops worth. I don't have any STDs neither does he, i don't have any problems down there everything is good but at the beginning of he can hardly get it in? and after i throb, like i can feel my ''area'' literally throbbing... I mean i'd understand if it was the first time but it's more like the 18th time.... why is this? Will ever be pleasurable for me? - just need to make it clear neither of us have any STDs just trust me on that.