cramping and bleeding but period not due for another week.

hey everyone. I have googled and researched a lot on what I am about to type in here but haven't found anything, hence this post. my period isnt due for another week but I have recently gotten my bc out (on the 1st of this month)and have had sex during my ovulation window this month as well as after. I feel really weak and have really bad cramps. I also am bleeding only when i go to the bathroom and wipe. could this be from the implantation of the fertilized egg? (I also took a pt 2 days ago and it came up negative).

~update~

I actually did get my period on the 14th of February.