Spotting Repeatedly

Has anyone ever experienced spotting repeatedly (as in every month, but at different times?)

The facts:

- Three months in a row I’ve had spotting 1-2 days before my period. The spotting always stops, and then the next day the period will start

- I had always been regular but this does correlate with the same month I stopped breastfeeding so that may affect it.

-I’ve had my period back postpartum for a year now

-This month I spotted two days ago and it was a lot less spotting, just pink and one or two hours worth of bathroom visit proof

-Three days later my period hasn’t started (it’s “due” in five days but it has been “early” by 3-8 days the past four months

-I DID take 2 pregnancy tests. One the day before the spotting because I’ve been fatigued and have had a low fever all week (we had a sloppy romance a few weeks ago so I thought there was a minuscule chance) and a day and a half after the spotting. Both were negative.

-I had my annual checkup a month ago with a ultrasound and physical (I have pelvic floor pain so they were making sure that was normal postpartum and not related to any internal issues-they’re super thorough). And all looked great and felt great according to my dr... just more pelvic floor weakness from pregnancy.

Any ideas? Thank you in advance!