advice pls, 16 y/o worried about pregnancy

i’m 16 years old. me and my boyfriend have been together for a while now and are very sexually active. i am on birth control but i’m very concerned i might be pregnant. i’ve been feeling very sick when i wake up and i’ll get really tired throughout the day and i’ve had bad stomach cramps and spotting which is not usual for me between periods. i’m on seasonale so i only get my period every 3 months. i just really need some advice from someone with more life experience than me. i’m terrified