In 20 minutes your blood pressure will drop back down to normal.
In 8 hours the carbon monoxide (a toxic gas) levels in your blood stream will drop by half, and oxygen levels will return to normal.
In 48 hours your chance of having a heart attack will have decreased. All nicotine will have left your body. Your sense of taste and smell will return to a normal level.
In 72 hours your bronchial tubes will relax, and your energy levels will increase.
In 2 weeks your circulation will increase, and it will continue to improve for the next 10 weeks.
In 3 to 9 months coughing, wheezing, and breathing problems will dissipate as your lung capacity improves by 10%.
In 1 year your risk of having a heart attack will have dropped by half.
In 5 years your risk of having a stroke returns to that of a non-smoker.
In 10 years your risk of lung cancer will have returned to that of a non-smoker.
In 15 years your risk of heart attack will have returned to that of a non-smoker.
So, you have more immediate things to look forward to if you quit now besides just freaking out about not being able to smoke. So quit now!