Sounds like what I have Buerger's Disease, you might want to look it up. Yes I have it and it is hard to quit smoking, I tried lots of times just to keep failing over and over again, I am afraid if I don't stop smoking Buerger's disease will get worse for me and I will end up with no legs.
I had a doctor appointment yesterday and I talked to her about the leg pains/cramps that people complained about after using Chantix and she said that leg pain happens because we smoke, not because we quit smoking.
I believe our senses are enhanced after quitting......looking for something that is out of the ordinary and perhaps that is what happened to you. Also, sometimes we will look for excuses to pick up a cigarette again, blaming it on anything or everyone else but ourselves and our lack of willpower. I'm not saying that this is what is happening with you, but I know I have been guilty of this in the past : )
Given your age, I doubt if what you are experiencing is serious, but perhaps it is more of a wake-up call.
Good luck to you and keep trying. You can do it........most of us have and lived to tell about it : )
Kathy Jo