Spotting 5 days before period. Normal?

No cramps or anything..it’s dark in color and it’s a decent amount. I don’t think it’s implantation at all..I hope. What could it be? Legit it’s never happened before. I’m not on bc or anything, no stds, I’m 20 years old and healthy, average weight.

I did have sex on the 17th but nothing else beside that. Used a condom. We had sex only once, no multiple sessions or anything. He was my second sexual partner. I’m a bit worried now 😅