I am experiencing neck, back and wrist aches, this has been on and off for months. When it comes on I feel like I need to frequently crack my wrists. When it happens it's very uncomfortable. What could this be?

Joint pains. Consider work up autoimmune status - swelling or just pain? - CRP, ANA CCP, sed rate , DS -DNA,. May be related to food intolerances , gluten soy , milk, test by eliminating those ingredients for a week in a step wise fashion ( i.e. 1 week no dairy , 1 week no soy ) check labels (lecitin is soy) Check for strep , UTI or vaginitis as, can cause immune rx. Check thyroid f/u /w/ rheumatologist.
Habit. "cracking" your wrists ( fingers, neck etc. ) is harmless- related to air trapped in the joint fluid bubbles "popping" just like bubble wrap . You should be examined for signs of joint diseases like osteoarthritis and rheumatoid arthritis. Exercise, do flexion and extension exercises and most of all stretch.