Pregnancy Scare

Cece
So i already had a 9 month old daughter so i know the process of making a baby, and what i'm worrying about may see stupid but i'm soooo scared of getting pregnant again so i'll sound stupid if it means getting answers. So for the first time since i had my daughter, me and my boyfriend were getting really close to sex. like we were naked and like rubbing on each other but he never went inside, and i'm really scared that his precum could've gotten me pregnant. i'm on depo as my BC and this happened a few days ago and i just got my shot today. some back story. since being on depo, my periods are like a month long each time, and i had finally gotten off my period and we decided to get more frisky than usual. well then yesterday, what i think is, my period started again. but i'm worried that it's not my period but it's spotting which is seen in early pregnancy. since there was such a short time in between the periods it's making me think it's spotting from pregnancy but my last month long period was super light too. and i don't know when it's the right time to take a pregnancy test and i don't want to take it at the wrong time and it give a false answer. i just can't be pregnant again. i already have a disagree and i'm still in high school and i'm just not prepared. and we literally didn't even have sex, i'm probably just worrying myself but i can't get over it.