I get what feels like a build up of pressure. at de back of my head sometimes?wat wood be de cause of tis?stress lack of sleep or something else?

Tension that builds: up in the back of the head or the neck could be related to either of those issues. To address stress: Talk about feelings & address problems. Don't avoid them. Aim for 7.5 - 8 hours of sleep/ night. Daily physical activity is optimal in a green space. Eat healthfully. Cut out junk carbs, caffeine & alcohol (or moderate). Try Qi Gong, Tai Chi, acupuncture, acupressure, homeopathy, meditation, Yoga