What Causes Cracking Sound In Head And Pressure On Back Of Neck?

Hi! I have been experiencing a cracking sound in my head on and off for about a month or so. Plus some pressure on the back of my neck and head, above my ear, also my fingers on my right hand go numb, as well. Is this a serious or what type of dr. could i go for some help. I would like to know where you are located.?