Hi guys I need your help. What would you do?

Basically long story short I have been with my partner over a year, I'm 26 and he's 37. He has a teenage daughter already and I have no children. When we first got together he told me he would like to have more kids at some point in the future, but recently I bought the topic up again and he told me he has no intention of having any more children and doesn't remember saying otherwise.

Now I'm in a really difficult situation as I have never been bothered about having children before, but since I've been with him all of a sudden I've got really broody and can't stop thinking about trying for a baby. I basically have 2 choices, either stay with the man I love and deal with the fact I likely won't have a family of my own, or leave and try and find another man to father my children. I don't want to do this as I don't want to panic and settle for someone who isn't right just because I want children.

What would you do?