New transmission whining, slippin

[blueaccord19]

Hey a while back my transmission was kickin outta 5th gear and eventually went out all together. So, after getting screwed out of $2600, im an idiot, for a new transmission and clutch, it is now screwing up again. It's making a whining noise from the transmission and now it has started to pop out of every gear. Anybody got any idea what it could be? I'm takin it back to the idiots that worked on it before to be fixed for free, but jus curious on any ideas. Is there a line from the radiator going to the transmission? Also does a manual transmission have fluid? I know it has clutch fluid that is filled from the engine bay but any fluid other than that? Also whats a reasonable price for a rebuilt transmission and clutch? Cuz i'm sure i got screwed over. Thanks for any help.