What could this mean, light period only lasting 3 days, pregnant?

I got my period on Nov. 16 sometime in the afternoon. Usually my period will last roughly 5-7 days and it’s always pretty thick. This month I got my period and it wasn’t as thick. It lasted for 2 1/2 days then went away. I had sex with my boyfriend a few times and there was no blood but oddly enough… I started spotting a few days later (Nov. 19th). The spotting only lasted a few minutes then it went away. We had sex again… no blood. But I spotted a tiny amount again!! I am so confused! I don’t even know if I should consider that a period :/

What makes me even more confused is I don’t see how I could even be pregnant. Okay… Ya I’m thinking the worst but what else could it be?! My boyfriend and I aren’t the SAFEST when it comes to preventing pregnancy but we do use condoms when we can. Most of the time we use the pull out method and we’ve never once, in three years, had a “ugh oh” incident where he couldn’t pull out in time. He’s really good at controlling it.

So what do you think? I couldn’t be preggo when he never ejaculates inside me right? And would you consider that a period? I mean, if I WERE preg. then I couldn’t get my period right? I dunno, my tummy feels weird too. Maybe I’m just worried. It’s like a queezy feeling, kind of nauseous at times but usually … just weird. I’m worried and any advise y’all could give would be great.