im scared i might be pregnant

im 17 y/o my bf and i had unprotected sex 2 weeks ago and last night my breasts urt so bad i couldnt sleep. ive had my nipples pierced for 2 years and they started to reject last night. ive been feeling Nauseous in the mornings but i havent thrown up.. my period is supposed to start in 7 days but im scared that it will be late.. im also very scared to take a test. i dont know what i will do if im pregnant.. my mom would kill me pls help