Confused

Hey! So I take my bc pill straight through and it stops my period. So I haven’t had an actual period since April sometime. Well my boyfriends been away and I wasn’t able to see him for about two months. When I saw him, we had sex and a few days later my period started? I’m confused as to why because I haven’t missed any pills in over a month so I dont understand why I’d be bleeding.

But the thing is when I started the pills it made my period outrageous and I’d bleed a lot and for awhile. But currently it’s not a lot of bleeding and it’ll stop for a day or two and then start again. I’m extremely confused as to what’s going on and wanted to see if anyone had some answers! Thanks!