Thought I should post that I solved my heavy head problem. For 2 years, my head felt incredibly heavy, like a bowling ball that my neck could barely support. No meds seemed to help, nor did occupational therapist, chiropractor or acupuncturist. Neck was stiff also. Lying down didn't seem to help at all. Felt like spine was compressed and I had the inclination to hang upside down to release the pressure. (Never helped.)
After way too long, I discovered it was the Adderall I was taking (for adult ADD). My discomfort was completely gone after going off of the Adderall. In the 18 months since I've been off of Adderall, I have, on 5 occasions, taken 1/2 an Adderall (10mg) to help me focus on various projects. Each time, the stiff neck, heavy head problems returned for several days afterwards. The Adderall also caused me to clench my jaw & grind my teeth at night, which could have resulted in the rest of the problems. Thought I'd share.