Methods To Quit Smoking

I quit smoking on Sunday night at 10pm. Today is Thursday, 4 am (I work night shift) I have not been having the dreaded nictoine withdrawl symptoms as I feared…then it hit me. Is the nicotine still in my system? And how long does it take before it gets out? I heard it was about 3 days that it took to get completely out?

I quit smoking while I was going into the second month of being on birth control and now i missed my period. I was supposed to get my period about 3 days ago and it still hasn’t come. I got it when I was supposed to my first month on the pill, so why did it skip now? I took a test yesterday and it said I wasn’t pregnant. I plan on waiting a week and if my period doesn’t show then I’m going to take another one.
Could quitting smoking be the reason this happened?

If someone were a heavy cigarette smoker for at least a couple years and then quit, would smoking a cigarette a month or two after getting over withdrawal symptoms from quitting get them hooked on cigarettes faster than the first time they became addicted?

I’ve been smoking for over 25 years. I smoke maybe 4 or 5 cigs a day, and I’ve stopped for 3-4 months at a time. But when the nicotine fit hits me, I can’t deal and start smoking again. What can I do?