Need advice!!

So my period is supposed to come tomorrow and I’ve been having all my normal PMS symptoms and stuff.

Yesterday went I went to the bathroom I noticed like a good amount (not like a lot but enough for toilet paper) of blood. It was pink but dark pink. I put a tampon in thinking it was normal period but then hours later the tampon had nothing on it. I did have sex that day so maybe it was from that??

I’m thinking it was too much/too dark for implantation bleeding but idk...

Do y’all think it’s from sex or just my period spotting early?