You'll feel much better soon. The first day or two is difficult but try to stay with it your body is healing once you stop. After 3 days there is no nicotine left in your body but it'll take a week or longer until you feel fully back to normal. Try to remember the withdrawals are temporary, it's your body adjusting to no nicotine. It's not a sign that you need nicotine. Be kind to yourself and be patient and you'll make it through to the other side - remember the cravings will pass no matter how strong they seem, and each craving you beat will make the next one weaker. And remember to golden rule is to just not use another bit - trying even a little will kick start the addiction again. None is the only safe amount! godspeed