Is it too soon to worry?

My fiancé and I have been trying to conceive the past three months. And so far nothing. As of this month I felt we had done everything right but from what it seems like, AF should be here tomorrow and I've been having slight cramps. Not bad as usual (I cramp very severely due to a cyst on my ovaries). I've also been having breast tenderness but that's usual for AF.  Which takes me to my other concern, I worry I can't have kids. I know we've only been trying a few months but it's starting to make me upset that maybe motherhood was something that wasn't meant for me. I'm not sure what else we can do to increase our chances. Or if somehow we aren't doing anything right. We are just at the point in our life where we want to start our family, being that I'm 23 and he is 24. I fear I can't.