Re: ***Splint Question***
My symptoms ranged from intense headaches, jaw pain, night clenching, sound & light sensitivity, tingling and numbness in fingers, shoulder and neck pain...
I'm certainly not a professional but I don't recognize any of your symptoms (except grinding) as TMJ. Also, lots of people who don't have TMJ do grind as well. I would make sure you get a second option from a really good neuromuscular dentist (see link above) before going into any splints.
Keep trying all options - sometimes if you get to in impasse with Western doctors, you may find luck in a naturopath or doctor of Chinese medicine. I've had particular luck with digestive issues going the alternative medicine route. Just make sure you see someone good. It's worth doing some research to find them!
It's hard when you aren't feeling well - but keep looking until you find an answer to your health problems. It may take time, but you can get there with enough persistance.
Best of luck!