Implantation orrrr ? Please help!

Okay so me and my bf have a very active sex life. My period is due on the 11th but on the 5th I went to the bathroom and wiped and had pinkish/brownish dc. I put in a tamp thinking my period was 6 days early (NEVER HAPPENED TO ME EVER). I went to the bathroom a few hours later and guess what? Nothing was on my tampon. I had cramps and sore boobs (light cramps). Now I have no cramps & my boobs itch like hell! (A little sore, not as bad as before). Did this happen to any of you guys and you were pregnant? Orrrrrr? Please share some advice.

P.S I definitely had sex on the 28th + 29th.