Unfortunately when quitting everyone has different symptoms. Some people find the surface of the scalp is very sensitive for a few days. Even touching or combing hair can be painful. This can be attributed to the blood pressure change as general circulation improves.
How long will this last? The first few weeks after quitting.
Tips to help: Use a soft brush, or ask you doctor or pharmacists for products that may assist you.
If you have a symptom that persists or seems worse than you expected, you should immediately consult a doctor. Its possible that your smoking has been masking symptoms of some illness, and when you stop smoking the symptoms abruptly become noticeable.