Whats wrong with my dragon??

Question
My bearded dragon just turned six and up til yesterday he was very healthy and active.Yesterday morning I left him in the window in the sun(He is not in a tank)when i went to work and came home to him sleeping which I found nothing out of the ordinary,until I laid down on the couch with him and he eventually moved,kind of slithering along lifting his head but in a weird kind of up and to the right sort of way.I just knew he wasnt acting right so I grabbed him and held him up and his head kind of seemed floppy,I gave him a bath and cuddled him,(also I could hold him belly up)....This morning same thing but Ive let him down on the linoleum and he had a hard time moving so I put him on the carpet and hes sort of just dragging himself.Im so scared and worried,its almost as if he broke his neck but he can hold it up....please help me...he means theworld to me....thank you....

Answer
Hello Shae,

I am sorry to hear about your dragon.
Let's go over your tank setup, to see if everything is correct.  It is possible that something may have been going on for awhile & his body just started showing effects.  They like to hide illness & do so very well.  
What type & brand of UVB light are you using?  Is it a fluorescent tube bulb or a compact/coil light?  How old is the UVB light that you are using, & how close it is to him?  What type of basking light are you using, a bright white light or a colored light?
What are the basking temperatures in the tank, & what type of thermometer do you use to measure the temperatures with?  A round stick on type, a digital probe or a temp gun?
Do you use supplementation like calcium or vitamins?  
What type of substrate is he on, sand, tiles, non adhesive shelf paper, carpet?  
Do you have a picture of him, in his tank, so I can see his setup?  
Based on his behavior such as slithering along & not being able to lift his head up very well, it sounds like metabolic bone disease advancing.  
I don't think that he would have broken his neck unless he fell from a distance & landed on his head/neck area.
What does he eat on a normal routine?

Tracie