Hi I’m sorry if this is a stupid question lol

I have been on birth control for about 8-9 months now. At the beginning every time I would go for a refill I would get a different brand of birth control or different hormone thing. I did not get my period last month nor did I experience any of my regular symptoms before my period. I took a pregnancy just to be safe but it came back negative. I continued my birth control and this month it seems like I won’t be getting my period either. I’ve had some cramping but not much other than that. I’m supposed to get my period this week, but I doubt it. I took another pregnancy just to make sure and again negative. What I’m asking is, is it normal to miss periods on birth control? If so how many or will it just stop until I stop taking them?

Again i apologize thank you for the clarification.