Am I pregnant?

Hey ladies! I am TTC and this month I am late on AF by about 7 days (haven't taken a test yet) doing it tonight. I am a smoker ( I know it's bad and I have been trying to quit and I am just about there), any who- I just went out on my break and had one- but I didn't even get threw half the cig before I started to chock and literally gag causing me to throw up!! Is this normal? Could I be pregnant and my body is telling me not to smoke!! Thank you!