so confused.. (miscarriage trigger)

I miscarried 2 weeks ago and the day after I left the hospital, I took one last pregnancy test and it was a strong positive, but sometimes last week i took a test and it was a faint positive then negative. I had sex last week wednesday, he didn’t cum in me, but some of it did go down on my vagina. I have been having a lot of discharge, not smelly or anything . I also been having cramps on my right side and lower back pain and sharp vaginal pains. I put on a waist trainer earlier and when i took it off, my right side was hurting and my stomach was just hard and that’s when the vaginal pains came in. I have been really tired lately like when I found out, i was taking naps. but I feel pregnant still.

When I first found out i was pregnant, i had sore nipples, i had HUGE hunger pangs. I was between 2-4 days late for my period and started heavy bleeding on Feb 16th with little cramps but they werent painful or severe and i was bleeding like a regular period, wasnt going through pads or anything but I went to the ER and they said my levels were below a 5 so I already miscarried.. or so they said. I got my test results back from my doctor the day before and he told me that my tests came back positive for pregnancy. But it was negative with blood and pee test at the ER. I tested with a FRER before the ER and it was positive, then the day after my ER visit, my pee test was a strong positive, but i was bleeding for 5 days after the ER Visit. I took other tests, i had one test that showed a faint positive and i took another frer that showed nothing. Besides that, I went to my GYN the day after i went to the ER and they didnt see a baby or anything during an ultrasound, i was only 4 weeks at the time.

I want to know if anybody has experienced bleeding like a period and never got their period the next month that they were actually pregnant?