What Causes Headache And Cracking Sound In Head?

Hi, may I answer your health queries right now ? Please type your query here... I am a 21 year old female, i have been having on off bad head aches for around 6 months, i am now getting alot of lower back and neck pain. Aswell i get a cracking/popping sound in my head, which feels like the noise is in my brain. I am awaiting an appointment for a mri and i am really worried. Is there anything you think it may be?