Implantation bleeding

Hi everyone, I am experiencing some red/pinkish blood. I am not sure if that’s implantation. I had my last period on Dec 16 and it lasted for 5 days. I was ovulating on jan 1-6 that’s what glow app said. On Flo app... I was ovulating on Dec 27-6 of jan. I had unprotected sex on Dec 28,29, jan. 1st, nd 4th. My next period is in 7 days.

Did that ever happen to anyone before ? And what made be some of the reasons? Am I pregnant? Cause I took a pregnancy test, it was negative.