implantation or nah?

i started bleeding randomly, it’s a strong red colour - kinda like a period and i passed a clot or some lining i’m not too sure but i’m confident in tjis just being breakthrough bleeding. i had sex on the 23rd of june and yesterday (29th). I am on the pill and my last period was the 15th to the 17th of june. So if i was to ovulate it would have been around the 28th of june. one of my nipples hurts but it’s too early for symptoms. he wore a condom and i’ve taken my pill consistently.

thoughts??