Update
Well, I think I figured out why Xaine has been having trouble with his weight.
Xaine had gotten a little but of a tummy upset, his droppings going way softer and smushier than I would approve of and he'd gotten a little lethargic over the late weekend. On Tuesday night I came home to a very floppy and flat chin. He was flattening himself out and rolling and stretching around. I immediately gathered him up and took him to the emergency vet, fearing that he may have developed bloat and he was in some serious pain either way.
He had to stay the night as the emergency vet, got some fluids and some pain medicine. I then took him to the vet clinic down the street from the emergency vet. They have one of the best specialists in an area about 1-2 hours from my house.
The vet was more wonderful than I could imagine in his handling and knowledge of my little guy, and I feel much more knowledgable than Xaine's current vet. He gave Xaine a little anesthesia so he wouldn't stress more than he was already and gave him a very complete look over. X-rays, blood work, teeth, fur, all the extra stuff.
As it turns out, my poor baby's white blood cells were through the roof and his red down. A little anemic too. Turns out, he has a little type of what the vet suspects is a chronic infection and that's why he's been having trouble with his weight first stopping and then fluxing like it's been. We still have no idea where or when he developed it, just that it finally caught up with him and started zapping his energy. So he's given Xaine some antibiotics and some appetite stimulant and he's eating Critical Care mostly right now.
Xaine is doing much better and is putting on his weight some finally. Needlesss to say that I have a new vet for him. My other was hesitant to do to much to him aside from paraside and general look over tests as he didn't want to stress him.
I still thank you all for trying to help him by home means, but someties I guess we all need a doctor. Hopefully he'll continue to put on weight and when he's more well the vet is going to try and boost his weight as well.