First off, it's AWESOME that you are trying to quit smoking. It won't be easy and you have all of our support 100%.
Nicotine adversely affects EVERY major system in the human body. As it builds up from regular use, it can lead to weakened immune function, fatigue, decreased healing time, and long-term diseases including cancer. In fact, nicotine prevents the body from properly disposing of damaged cells, thereby allowing cancer cells to develop.
Nicotine is also extremely addictive so trying to quit cold turkey might not be the best idea. You could try nicotine gums, patches etc to try and help you get past the withdrawal symptoms.
Book an appointment with your doctor. He will help put together a treatment plan with you to get off the cigarettes for good!