short lasting light period, sickening smells,

I am 18 years old and I came off the pill about 2 months ago. Me and my boyfriend have not been trying particularly but we just thought we would see what happens, we have sex near enough every day at least once, usually twice if we are in the mood.

my period was 6 days late and when it did come it was very very light, (still red though) and I'm normally a super plus girl. It only lasted about 3 days which is unusual because I am normally on for 6 or 7 days at least and have been known to bleed for 10days.

The only other differences I've noticed in myself are I'm always thirsty therefore drinking LOADS more water and therefore urinating more. I also nearly threw up the other day because the smell of the chicken I was cooking was repulsive which seemed unusual but thats it. Maybe it's just my cooking?

Anyone think I could be pregnant? I would take a home test but it would be on such a wim and I know i'd be disappointed if it was negative!