Birth control question

I started the birth control pill (lo lo estrin fe). I am 5 months pp, regular cycles for the last 2 months. I am 3 weeks into my pack and I’ve had spotting for a week and then woke up today to HEAVY bleeding and cramping. Is this a true period in the middle of my blue pills? I’ve never gotten a period on birth control pills before so I’m confused as to why I’m cramping and bleeding like this.