Smoking as a pregnancy sign??

So I smoke, not a lot but lately it has been every few days I would enjoy a blunt a day. I've been smoking for more than 3 years now but lately anytime I smoke, i feel super nauseous. I never get sick from smoking.. So I thought it was just because I hadn't smoked in a few days but tonight it almost made me pass out and I ended up throwing up. There could be a chance that I'm pregnant, although we aren't trying or using protection. Just curious has this ever happened to anyone as an early pregnancy sign? I won't be smoking again till I can figure out what's wrong with me. Testing tomorrow