Unable to push with uncircumcised penis.

Hello doctor, I've been married for 6 months and been trying for pregnancy for 2 months. During sex, when my penis enters vagina, my foreskin automatically gets pulled back completely and the exposed head enters into vagina. Then I can able to push a little more of my penis inside but if I go deeper, my retracted foreskin causing pain as it can't be pulled further. Also wife says, penis is hitting something at her end only when my head and some of the middle shaft enters into vagina. Is that enough to hit cervix? It would be around 3 inches. Why I can't go deeper even with completely retracted foreskin? Is this normal? Am I really hitting cervix during penetration? I am ejaculating inside vagina at the furthest point I can and when I take my penis outside almost half of the semen flows out. Is this enough to get pregnant? Please help.