Implantation bleeding or period

Steph
Okay so I had intercourse with my bf on the 7th which was one of my highest ovulation days. We also did it again the next day. My next period isn't expected until the 23rd. Today (13th) I went to go use the bathroom and as I went to wipe I saw this red/brown substance on the tissue. Could this be implantation bleeding or a start to an early period?