My Period Haven't Came On In 2 Weeks And I've

my period haven't came on in 2 weeks and i've been feeling tired, wanting to throw up, light head (headache), my stomach been acking and feeling weird and ive been wanting to eat alot of big mac sauce from Mcdonald's and i took a home pregnancy test yesterday and it came back negative i don't know if i'm pregnant or not . im only 17 i cant be pregnant.