During afternoon following a highly active day I find I start yawning, develops into headache in forehead, some irritable moodiness, no increase in thirst, hunger, some tightness in neck and back, need to lie down. Sometimes also light / noise sensitive. Has been a rare but ongoing occurrence since teenage years - now 41 yrs. Last time it happened also vomited, and cold, shaking. Often Panadol has no effect and I just need to sleep it off. Any suggestions would be helpful - my GP said just come in when it happens next, but last time we were camping hours away from town. Connie