Dandruff/Scalp. After shave. pls help.

Dear Dr. I have had dandruff for many years. I use H&S shampoo. It keeps it somewhat under control. But recently it has been on the rise. One Dr prescribed Tarry Shine shampoo. It helped for a while. But it's gotten worse. Apart from that, I'm balding due to hereditary. On a bald patch, I've got lots of dry scabs forming and itchy. When I scratch it comes of and a white watery substance oozes for a while. Then it dries up. I've got this on the back of my head a little above where it balds usually for men. Also I've got two small patches in front of my receding hairline. I also have a small patch that's growing a little left below my left eye on the cheekbone. This is whitish scab then becomes brown. It's itchy and dry. Then the scab becomes loose and falls. It keeps repeating every 3-4 days. I feel itchy on my chest & have some dark marks. I'm also hairy. I drive a car. I'm outdoors now and then. I don't drink or smoke. I'm clean shaven everyday and use after shave. Pls help.