I've been spotting the last couple days...??? (Read the details, please)?

Okay, so I started spotting a couple days ago. Very random and not constant. I shouldn't be starting my period for at least another two weeks, and I've never had an issue with my period. It's always right about on time, same time every month. I've never had spotting. It's mostly light pink, sometimes with a couple drops of darker fluid. I'm not on birth control, haven't been for years, and my boyfriend and I don't use condoms. I've heard of implantation spotting, or whatever, so I don't know if that could be it. I asked my mom though, and she said maybe I've had a miscarriage. However, we've only been having sex for, like, three weeks now.

Is that even possible to have a miscarriage after only having sex that long? What is the likeliness of that? And what is the likeliness of it being implantation bleeding?

I'm kind of freaking out here. Not about possibly being pregnant though, 'cause we want a kid. That's why we don't use condoms. But after my mom mentioned miscarriage, that scared me.

Any information or help or stories of others who've experienced this would be VERY MUCH appreciated!!! :)

Thank you!