Could this be implantation bleeding ?

Hey ! I'm new to this, I hope y'all can help me out. So according to this app along with another <a href="">period tracker</a> app I have I'm supposed to have my period in 11days. I've NEVER had any spotting or cramping in between periods but last Wednesday the 14th I started feeling period like cramps and noticed some pinkish discharge when I wiped after urinating. That same day, I noticed some light brown&pink discharge at night after urinating again. I thought I was about to have my period but it didn't come. Two days later on Friday the 16th again, when I wiped I saw some white discharge with a strip of bright red blood. I want to add that I have been having unprotected sex for a while now and I am not on any birth control. So my question is, is it normal to have this kind of discharge between periods or could it be implantation bleeding? TIA