I like to go to gaming events and play four or five games in a row, but I often find that I have a bad headache after just one or two. I don't know if it's dehydration or lack of food or eyestrain or what, but I do know that it is quite annoying and adversely affects my ability to make good decisions and get along with other players.
Does this happen to anyone else? If so, what do you do about it?
Neck possibly from looking down at the table. Neck, shoulder, upper back. Get up from the table and stretch some. The same rules as for sitting at a computer except that you really can't adjust the game to your eye level like a monitor.