I quit smoking, but i feel really weird.?

I quit smoking about 2 days ago an its driving me crazy. I'm 20 an i smoked for about 5 years. I smoked about a pack a day. I just quit cold turkey 2 days ago because i found out its preventing my stomach from healing from a recent surgury. I feel really weird. I feel really congested, i cant stop caughing, an i keep getting headachs that last about 10 minutes threwout the day. An im also dreaming about smoking cigarettes. When does all this stop?!?! I will pick best answer.