Do y’all ever get scared that you may never be able to have kids

So recently I have been thinking about this. I’m only 21 yes I know I am young but I don’t care and even more reason why I am worried because I feel like I should have had a successful pregnancy by now. Me and my husband have been TTC for 2 years. I have irregular periods, I do ovulate. But not regularly and so far no luck besides we did get pregnant once but miscarried 😕 I try to remain optimistic. I’ve just always wanted to be a mom. And sometimes I think about, what if I am not able to have kids? Could I be happy in my life and feel fulfilled without being able to experience motherhood? I don’t know. It really is difficult to think about. We are open to adoption but I have just always wanted to experience pregnancy, giving birth, having a biological baby.. I know I shouldn’t be thinking negative like this. It’s hard not to sometimes. Anybody else think this way? How do you cope and remain optimistic?