You've explained it fairly well, and yet I assure you I'm not certain without a visual look, but because you mentioned it hurt you or was sore, it makes me wonder if it may be a mere accidentally inflamed or bitten cheek... Might that have happened? It sounds, due to it's location, in the cheek, to be much less likely to be an abscess
. And yet, because of no visual, because we don't know for certain, but yet it hurts, I would recommend going to your Dentist
of choice for a quick x-ray or two, and it can be more positively identified.
Occasionally, we bite our cheeks, even while sleeping, and it "could" be such. But, in truth, without a visual, it's difficult to be certain.
I would doubt that it has anything to do with smoking however. And I wish I could be more specific, but I'd have to see it.
Use your judgement here, if it's improving (day to day), I'd not worry or be too concerned. If not improving and/or getting worse - see your local Dentist - OK? I hope this helps you at least some!
Don't hesitate to ask any follow ups, and/or if you find a way to send a picture, please forward it - alright? Thx!