Implantation bleeding?

Monica
Need some advice. Thursday about mid day I went to the rest room and had bright pink blood when I wiped. It was about a week too early for my period. I continued bleeding until Friday, alternating between light and moderate, always mixed with a brown discharge like at the end of your period until it tapered off to just a small amount of brown discharge. I had cramping on and off Thursday that felt different than my normal period cramps. I've read about people having heavier implantation bleeding but I'm not sure what to believe. Other than that I have been very tired and bloated feeling, but also get those symptoms with my period. I've taken 2 tests that were negative but it is still prior to my normal period time. My husband and I are not actively trying to conceive but there was an "incident" during my fertile window about 2 weeks ago. Any insight as to what might be going on would be appreciated.