Does Delayed Period And Vaginal Spotting Indicate Implantation Bleeding?

Hello,

I have some weird things going on with my cycle and I am curious whats going on. I have missed my period for 2 months up until 3 days ago. I assumed I was pregnant because I have been before (last time it took me 4 months to get a positive home test). Going off the assumption, my boyfriend and I have been having unprotected sex. Maybe not the wisest choice, but we did. 3 days ago, I got what I assumed was a period. Only thing is this, I bled for a day and a half and it wasn't like a normal period for me. It was very bright red and was very liquidy almost like water. No clots, no tissue, nothing. After that day and a half, I have been spotting off and on for 2 more days. I have been told by some people that it could be "implantation bleeding" or that I may have misscarried. I am not sure which.
I do have 2 uterises. So I am not really sure how to take this. Maybe I have an extremely late period that is just very irregular? Or is something else going on?

Thank you,
Amber