someone please help me figure out what is going on!!

Ok so I had a normal period October 5th-9th. Had unprotected sex on Wednesday October 12th, then I start approaching my ovulation days the next few days, I started bleeding on Sunday October 16th. This was very confusing bc I thought this was my ovulating time.. so I took an ovulation test and it had a smiley face. So today (oct 17th) I'm still bleeding just a bright red and not very heavy... could this be implantation blood? I'm so confused bc I thought since we had sex the 12th and sperm can last 5 days inside and since I ovulated yesterday that implantation bleeding would be too early????? So confused ...