How can i know the difference between implantation bleeding and just a weird period?

okay so it’s a really weird question and i find myself beyond stupid for having to ask this at this age. so about five days ago i started getting cramps. its around the time i’m supposed to be getting my period but normally i don’t get cramps.I’m still young, turning 16 in april. so i figured this is normal seeing as my body is changing. then, about two days later i got a tiny bit of brown blood in spots. this kind of freaked me out. normally its heavy the first days and this was just basically three drops all day. and, please dont judge, me and my boyfriend have been using the pull out method because we ran out of condoms and his parents (which he had asked to buy condoms) wouldn’t buy any for us. and neither of us could go out and buy some. we were only doing it for awhile and pull out way before anything happens but once we were very close to not making it. anyways, so knowing that i was really scared. and then the next day there was a lot more blood and i had to put a pad on. by the end of the night it was bright red and normal. but now its still heavy but it’s back to brown, but maybe its just because it has been sitting for a bit? i still see bright red when i go to the bathroom. maybe i should wait a couple days and next month to be sure? i cant take a pregnancy test. and me ans my boyfriend are going to stop being crazy kids and stick to safer things from now on. (im also not on the pill. side question; how can i ask my mom without her thinking im having sex? i dont want her to know unless she has to)