What Causes Headaches While Having Dent In The Top Of Head?

I have a dent in the top of my head and it gives me very bad headaches, and when I touch it it feels as if my skull is very soft in the spot. The headaches last for 3 to 4 days. If I press on it lightly,iI go blind and death for about 20 minutes. Is it something bad? Everybody tells me to go to the doctor very soon cause it can t me a good thing. Please help me find out whats wrong.