I'm sorry, but I can relate. I have been seeing my dentist for my jaw-clenching (related to stress) for about a year now. I wear a bite splint (best money ever spent) daily. However, there are times where this does not stop my clenching.
My clenching causes everything mentioned: jaw pain that radiates down my neck to my shoulders, headaches (daily), uneven bite. My dentist did an occlusion (sp? but this is= adjusting my bite by grinding my teeth down). Didn't work.
I see a craniofacial specialist in July. I just want some darn Percocet sometimes, but I know better and I know that is just temporary relief that masks the symptoms.
I take Effexor XR and Xanax PRN. I also have Valium PRN (this is useless to me).
I purchased some Lavender essential oil that I carry in my purse and rub on my neck and jaw. I take ibuprofin, and I also use an ice pack.
It sucks, I hate it for you.