Cryptic pregnancy. It cryptic pregnancy?

Doctor I need help. I've always had regular periods. Every month I used to get it. But after my first intercourse in march when it was day I finished my periods, next month I did not got it for the very first Time. So I took deviry for very first time and got 3 days periods. Also did beta HCG test 1 day before my periods and it was 1.2. I did each and every test all were negative. In june for the first time I saw fade red line on urine test. So I did beta HCG test again it was 1.2 I took deviry again and got periods. I also took ultrasound to be very sure about it at 15 weeks after this which said possibility of polycystic ovaries. I'm not getting my periods this month with the medicine! Is it cryptic pregnancy? I've read a lot about it that it doesn't show on ultrasound either. Women says they've gone through this. And seeing all this happening with me for very first time. I also notice some kicks and have to put pressure while constipation. I'm so scared.(never been sexually active)