possible implantation or something else?

So I have a question for anyone and most importantly women who have had children. And sorry I don't know the abbreviations for any of this stuff. 
Anyways, I have had two days now of very light spotting to where it's only on the toilet paper after I pee and I don't need a pad or anything like that. My bf and I had intercourse a few days last week but one he never pulled out. And I'm not on birth control bc of health issues I've had with each type they put me on. I don't have a uti/yeast infection so it's not either of those and it's it dry down there so it's not vaginal dryness. 
My breasts are almost always sore, I haven't had a headache and some very slight cramps but that's it. My period is due in a week and I've never had it bleed like this so far before hand. We've had unprotected sex before hand where he doesn't pull out but the bleeding has never occurred. 
So my question is, could this be implantation bleeding or something else? 
I would talk to my mom about this stuff normally as I'm 21 and still learning a little but she recently lost her best friend and don't want to overwhelm her until I get a few responses back and something is set in stone if what this is. So I would really appreciate some feedback! 
THANK YOU IN ADVANCE☺️