Oh, sounds bad, I am sorry! Maybe it's a physical issue? How does the saddle fit him? Maybe a chiropractor could come and look at him? What does he eat, maybe he is getting food that is too high in energy? Sorry about that martingale! Wow!
Hope it gets better... FAST!
I <3 you Magic!
He knows when you're happy
He knows when you're comfortable
He knows when you're confident
And he always knows when you have carrots.