It may be that you are already having PMS again, which could explain the cramping. There is no way to tell you if you are going to have trouble conceiving. Having PMS a couple weeks before your period is not that unusual, it seems, and by itself should not worry you about becoming pregnant.

Some information out there says if you haven't conceived in six months you should go to your doctor and make sure you are ovulating and nothing else is wrong, others say to wait at least a year. It will depend on you and your partner who also will help determine conception and may eventually need to see a doctor about fertility.

Right now though, you have just begun. It's too soon to worry. Though if you have specific worries, your gynecologist is your best source of help and information about you and your fertility health. I wish you both the best of luck!