My cat is about two years old and is both an indoor and outdoor cat. [He's almost constantly outside in summer. We keep food and water out constantly for him.] Today I opened the door to see him on the porch, so I let him in. But as he stepped over the threshold he could barely walk! I guess you could say that he was staggering. He didn't seem to be lame on any particular leg. I looked all over for wounds or abnormalities and felt for breaks, but nothing. And as I checked him over and brought him food, I noticed that he almost couldn't keep his head still, he kept slightly moving it in all sorts of directions constantly. Not looking at things, just moving in a really jerky way. And a little newer, I was stroking him and he had this weird spasm of sorts... like he just flipped out and his limbs shot out in different directions like he was jolted, and then he tried to walk over to lay down. I'm really worried... We're trying to figure out if we should take him to the vet immediately [hardly affordable] or what..