Likelihood of being pregnant 5 hours before period.?

If you got your period just hours after the unprotected sex then there's pretty much no chance that you conceived. You would have ovulated about 2 weeks ago, and there's zero chance the egg would still be around at this point. So if all of the factors you listed are correct then I would say you have about a less than 1% chance of being pregnant.

The time when you are most fertile is at ovulation, which is usually 8-14 days before your period. The chances of you ovulating after this are very low. Also, an egg only lives for a few hours, a day at most. For it to be fertilized, you need to have sex either before or exactly at the time of ovulation. Implantation would not occur for another 8-12 days.

Since you had sex just hours before your period, there absolutely was not time for an egg to be fertilized and implant. Unless something really crazy happens, there's pretty much zero chance of being pregnant.

You got your period. You are not pregnant. The cigarettes are not relevant - they don't make you infertile. It's just that having sex a few hours before you period is a highly UNlikely time to fall pregnant, since you ovulate 14 days before that.