I am usually very regular, 25 days in between cycles then I start with medium flow, nausea, and bad cramps first day, bad cramps and super heavy flow second and third day(and of last year, larger clots) and medium to light on days 4&5. This month I was 15-19 days late (can't find my tracking calendar so not super sure, but previous cycle was over before sept 24). I took two pregnancy tests on 10/31 and Nov 1 both very definitely negative. Started on 11/2 with typical cycle. On 5th day (yesterday) I was home sick with cold and went to use toilet and suddenly had massive cramping (sort of a mix between menstrual and gas) and broke into fold sweat and felt faint. Day on ground, felt a bit better but when I wiped I had a decent amount of brown discharge plus a bit of pinkish tinge as well, it's not unusual to have brownish discharge on my last day, but usually it's much less and very little cramping. Had cramping and more discharge for rest of day, all night last night and still today (what would be day 6). I have an appt with OBGYN Monday am, but in meantime--miscarriage? Ectopic pregnancy? Implantation bleeding? What is your best guess? Today's cramping is in lower back and pelvic area (more like ovulation pain than menstrual).
If it makes any difference I am 29 and usually super regular but I suspect I probably have endometriosis or cysts since I have pain during intercourse and always very painful and heavy during cycle.