What Causes Missing Periods, Bloating And Sore Breasts?

hi,i am 19 years old and my period has not came all this month.i have been bloating, and having sore/swollen breasts. my nipples are darker,i've been getting that carsick feeling while im not in a car.i'm having abdomenal cramping.my nose is running and conjested,and i have headaches. could i be pregnant?!?!?!?!?!?!?!?!?!?!?!?!?!?!?