Spotting Followed By Pregnancy Symptoms. History Of Having Unprotected Sex. HPT Negative. Habit Of Smoking, Drinking. Possible Pregnancy?

me and my fiance are sexually active and don't use protection (we use the pull-out method).i had my period, then started spotting and have a lot of pregnancy symptoms like nausea (everything smells gross and tastes funny), i usually hate sweet things but am craving chocolate/cake/caramel all the time now, and i've been having headaches and cramps.

I did a couple home pregnancy tests and all of them have come out negative. I feel as if i am, but we haven't been trying to have a baby (and neither am I, but wouldn't mind). Its just that i smoke and drink every week so don't want to put the baby at risk if there is one.

What should i do? it's been a week since the spotting and still negative results, could i still be pregnant?