i hope i'm just freaking out

hi. i had sex for the first time almost a month ago. for the past week and a half i have been feeling really weird. i had a little bit of bleeding for a day, i've been having light cramps, and my breasts hurt really bad. i have never had any type of spotting before or this kind of pain in my breasts. also the past few days i've been nauseated after i eat. i am not suppose to start my period for 5 more days. is it possible that i'm pregnant or am i just having the first time freakouts?? please give me some advice.