Endometriosis? Pregnancy? PCOS?? HELP

Okay so I’ve always had regular periods 26-28 day cycles, my periods were always 4-5 days, about last year they started to become shorter from 3-4 days which I figured, no big deal. but this month I’m scared. I started getting brownish discharge on Friday March 6th, which to me indicates my period is in town, then March 7th of course miss Bloody Mary had arrived, heavy, dark, and full of clots. Then yesterday March 8th, hardly anything, not even enough to fill up a pad. & today March 9th, nothing nothing at all. Why? I would go to the drs but my jobs insurance is no good. I’m only 22 and idk what’s going on. Also, I did have unprotected sex on feb 14 but he used the pull out method .. I had a pregnancy test lying around so I took the pregnancy test 7 days BEFORE my period (which was not late) because I was having a bit of odd pms symptoms that I usually don’t get, like breast pain, frequent urination & nauseas so i took it thinking there could have been a possibility but it was negative & i know it was to early to test, but i mean I got my period when I was supposed to, & it was heavy with clots so implantation bleeding should automatically be disqualified right? (Also no more symptoms) so can someone please give me something?? Google is no help & I called my insurance dr and she said “let me know how next months period is” which is why I mean they’re no good cus like ???? Really dr I’m concerned and she’s making me wait until next month. Can anyone help?? Any suggestions? Should I be more pushy with my dr?? Can it be endometriosis??

My biggest fear is to one day not be able to have children of my own and I really hope this isn’t a sign of that .. pls help 😞 any advice??