Welcome to ECF and congrats on your desire to quit, that's fantastic. Cravings can certainly be real in the beginning, I had plenty of them, and had to do various things to get to vaping only. Upping your nicotine may help, but there are other substances in tobacco that you will be detoxing off that may cause cravings and other weird feelings. They pass, if you want to tough it out. I'd agree that maybe upping your nic could be of use. They do make various "specialty" juices that can help with cravings (nic salts and Whole tobacco alkaloid juice) but since you have gone 8 hours without a cigarette and are hanging tough, I'd think maybe upping your nic a bit and reminding yourself that detox WILL pass (I believe 2 weeks is a number I've heard during several "quit smoking" classes I took) although personally I had cravings for longer than that, although they were more psychological in nature, but about 2 weeks smoke free things WERE easier with me with vaping.
With that said, I was a 3 ppd smoker, so I did need some added help while w/d and also dual used for a couple of weeks. It's really up to you what strategies you feel you should try (if any) but best of luck and welcome to ECF! Quitting is a journey but once detox passes, vaping becomes even MORE wonderful so hang tough if you can, and if you slip up, just return to vaping. Vape vape vape (before and after each cigarette) and count the ones you don't smoke, not the ones you do.
Anna