Clueless - periods and sex

Lucy

Hi all, I'm 34, ttc for the first time. Came off cerelle on 1st Jan. Since then I've only had 2 periods, one in feb, one in april. I've been on the pill since I was 16 so I have no idea what's normal for me. Do I need to have regular periods to conceive? Or is some enough? My last period was in April, and I'm not pregnant. We are having sex about 3 times a month. What is considered "regular" and at what point do I need to see a doctor, if at all?