i let the love of my life go for the very reason the OP talks about, she didnt want kids ‘right now’ but she wanted to in the future and was aware of the ticking clock (we were both 30ish at the time) i would have done anything for her and that included sacrificing my own happiness for hers.
i told her that adoption was an option but its different for women, there is that biological hunger
didnt see her for a few years but we are good friends again now. she now doesnt want kids any more but the breakup was very hard on both of us so the magic we had is too badly tainted for us to get back together.
i would say that unless you have given serious consideration to having a vasectomy then you know that you at least possibly want kids. tell her that, tell her its a maybe. who knows what the future holds, maybe you will begin to really want kids in a few years, maybe she will change her mind, maybe you two wont be able to have kids. maybe you will look back at this thread with a nipper on your knee and laugh at how little you knew 10 yrs ago. (im constantly amazed at how i was 10 yrs ago, i will be agian 10 yrs from now)
if she is yearning for children with you then you are making her feel happy and safe and comfortable. if you are deliberating so much over the issue then you will make a good father as you obviously care. not everyone does.