What Causes Headache And Nose Bleeds?

Hello, I currently have Sporatic Autosomal Polycystic Kidney disease; However, recently I have been recieving mild headaches and mild nose-bleeds. I have been a little unintelligent lately -- I have eaten a decent amount of protein in the passed two days such as extra cheese pizza, venison and burgers. I have an appointment with my doctor and neurologist soon. Yet, I would like to know if this is serious or not.