After the lasik eye surgery, the eyes pressure may not be stable. You should take care of the eyes very much. Or else, the unstable eye pressure and eye blood circulation could cause the headache. You'd better protect the eyes carefully. You should not smoke or drink, keeping the good habit of hygiene and life habit. You should do the eye exam at regular time after the lasik eye surgery in case of the eye problems.
Generally speaking, we do not have headaches after the surgery. However, it is a sign of health hazard, so you have to fix the problem. It could be resulted from some infections in the eyes, or an eye strain. It could be complicated, might be derived from other diseases. Anyway, It would be wise for you to have a medical exam to see what happened so that you could take better actions again the problem.
After Lasik and similar laser eye surgery, patients sometimes experience temporary problems with focusing, perception of distances, eye strain, headaches, fatigue, vertigo, even nausea and dizziness. These normally temporary symptoms may be related to the sudden change of optics created by Lasik or Lasik dry eye.