Late period

sam

So I’m like 3-4 days late and I’ve had no pregnancy symptoms or pregnancy symptoms I bled for a little bit 2 days ago “after s*x” and bled for a lil the day before that but it was like a brown pinkie stuff so I assumed I got my period but right after I bled for a lil 2 days ago it stopped and has been nothing…could that have been implantation bleeding? Or is my period just very late? Ps. Period has never been late like this..