I've been a 3+ pack a day smoker for 35+ years. Haven't had a smoke for 45 hours.

Congratulations, very hard thing to do, problem is you’ve got to relearn everything you do and do it without smoking, keep going, you’re really over the hard bit, 2 full days is great going!
The hours will turn into days, the days will become months and before you know it, years. How do I know, well I went through the same thing once and now it’s 28 years since I stopped!