Recurrent PID..need advice

When I was 17 I developed PID the first time that came from a chlamydia infection the year before. I had no symptoms I think I had it about 6 months I took some antibiotics but the pain was still there so the doctor prescribed me some more but within a day or 2 of taking the second lot the pain had gone so I stopped taking them as I believed the first tablets worked. A year later I started getting pains again, but this time on both sides painful periods pain during intercourse and low back pain. So I took some more antibiotics and seem fine again. I am 19 now and have been with the same partner since I was diagnosed the first time and we have never used contraception as we want to be young parents. We have been together 2 years and no pregnancy yet although my doctors say it's unlikely to have me infertile at my age. I have lost 3 stone and have irregular periods due to stress to this and really want to start a family but so worried. Docs say it could just be my periods and stress not letting it happen. My ultrasound looks fine. Any advice?I'm driving myself insane :(