Implantation bleeding?

13 DPO today. AF due today but no sign of her. Could this be implantation bleeding or just the normal spot before period? I do have regular 31 day cycles and this one is confusing me! Usually when I spot AF usually follows not too long after spotting happens. I’ve been having this spotting(only when I wipe) all day. My fingers are 🤞 but I’m trying to keep calm! hpt are negative.