Implantation bleeding?

Cheyenne

I had unprotected sex the 11th and my period is supposed to start in 2 days. This afternoon I had a little bit of brownish discharge in my underwear so I used a tampon. I went to go change it and there was barely any brown discharge on it with really really light pink spots on it and I haven’t had anything since then. Could this be implantation bleeding? I never had it with my first and my period is always on time and it’s never like this.