You sound stressed out. My neck and shoulders are usually tense most of the time. Sometimes as hard as rock...and nothing but muscle relaxants really seem to work. Even the strongest massage doesn't usually do much. My friend called it a frozen shoulder. I used a lot of hot rub products when it gets really bad, or a muscle stimulator. I believe it is our autonomic (automatic) nervous system doing it, and I don't think you can do much about it except relaxation exercises and medications.
My neck has been cracking alot lately because its so tense. Now when I look at my computer (I'm at work) I feel like my neck is gonna jerk and it sometimes does which makes me think I'm going to have a seirzures. My eyes also feel strained and I feel so jumpy. Anyone get this? I know I must sound crazy!