Found out some more infomation:
Tucker was bad last night with sucked in sides and jusy lying down.
This a.m. he wasn't too bad due to having the IBP, but still had sucked in sides.
While at the vet all day he was perfect ..running around and eating ..but my vet said he did notice that he never drank or pee'd.
When I went down to get him, my vet took his temp with a therometer up his bum, his temp was normal ..he gave him a shot for infection just incase there was any infection and gave me some metacam just incase.
When I got him home ..he was completly lifeless ..and thats when it started
My vet says this same thing happens to g pigs, when the neuter is healing, a piece of abdominal fat attaches itself to anything thats near it ..but he hasnt seen it in rats before ..and he has had his fair share of rat neuters ..its so confusing.