after sex question when ttc

So my husband and I have been ttc for 8 months now. And I've noticed since we've been trying a lot of times when he "finishes" inside me, I wait about 15-20 mins till I get up , or even sometimes a few hours to get up and every time so much of his cum comes out of me when I wipe. Is that normal? It makes me think that none of that is going up my cervix / uterus . Thanks in advance!! :)