I've been smoking this month, and having a lot of stressful days ..im really scared to miss my period, i had protected sex he did not ejaculate.chances?

Contraception: There is always a chance of pregnancy if sperm comes in proximity to your eggs. If event occurred <72 hrs ago, Plan B is an option now. Take a pregnancy test if your period is late. Get in to planned parenthood or another clinic for birth control and start right away if not pregnant. It sounds like addressing your stress/mood may also be helpful.