pregnant?

My period is 4 days late. Me and my boyfriend have sex. We don't use a condom but I've been taking birth control for 3-4 months. The very beginning of this month I was sick and didn't take it regularly and was thrown off track. Is there any way I'm pregnant or is this normal? I'm new at this whole thing and am slightly freaking out. I don't have any symptoms yet for pregnancy. Any advice would be great ☺