You can do it!
I'm on day 26 without smoking now and going strong! I can definitely understand how you feel right now. Everything Irene says, I second. Especially the bit about imagining the phlegm - bleeeegh.
My dad was a smoker for 15 years and quit cold turkey, luckily on my 3rd day of quitting he was visiting and he gave me three good bits of advice. The first was to treat your pangs as reminders of how far you've come. So rather than thinking about how badly you need a cigarette, think instead about how that pang is a reminder that you have managed to go x many days without one. Secondly, whenever you're with people who are smoking/see people smoking on the street/on the TV, think to yourself "what a sucker." It seems callous but you just need to say it in your head, associate smoking with negative things rather than anything positive. Finally, if you're offered a cig on a night out, say "no thanks, I'm not a smoker." This one I find a bit odd, but I see the sense in it. You need to disconnect any identity of being a smoker from yourself.
I've been using
an app called Smoke Free and I've found it so useful. It gives you tasks for each day, a diary to fill in noting your cravings, and a timeline showing you things like when nicotine is totally expelled from your body, your circulation should be back to normal, your risk of a heart attack should be back to normal. It also tells you how much money you saved (and you can set yourself reminders to buy something you've been wanting for a while once you reach a certain target). I find the whole thing really motivating!
Good luck!
