stressing for nothing????

my boyfriend and I who've been together for almost a year now have sex a lot and I'm on birth control but my periods are so light and short. I've been really good about taking my birthcontrol around the same time every day for 3 months now. usually we use a condom but we've gone without one a few times. I'm scared I'm pregnant. I'm not supposed to get my period for a few more weeks but I feel like I should take a test. is it all in my head? it's really stressing me out. I'm only 16.