Head stiffness center of forehead. Up?

Specially after lunch from around 4 pm to 9 pm, i need a stiffness and numbness at the center of forehead, which around the eyebrows. Eyes feel very tired. It triggers more when I am driving. Sometimes i feel slight pain at the two ends of forehead. I have specs with power -2. Eyes power has not changed. My dad starts with coffee then slight breakfast, the lunch around 2 pm, then coffee around 4 pm and so on. I take nexito ls half a tablet thrice a week. Otherwise i feel brain zaps at the two ends of the forehead. Also I get gastric issues many a times. Feels like gas trapped in stomach. I don't eat too much carbs. Neither too much junk. I drink whiskey twice a week. Around 200ml. I smoke cigarettes daily around 5-7, but not the whole cigarette at one go. What should I do? Is it because of stress, or tension or some nerve issue or gas that goes up? Please help.