help help

my period is 7 days late and i’m kind of freaking out. This month i’ve lost a bunch of weight and gained it all back over the course of the last few weeks and i also had sex with a condom 3 times within this month, twice right before my fertile window. im also having stomach pangs a few times a day and i’m not sure if i’m just being paranoid or not. im really scared, please let me know if you know anything. Im 17