Automatic transmission revving high

I took my 2002 2.4L Tacoma in to the shop a few days ago to fix a transmission leak. Under a quart of fluid was all that came out of the tank. So they changed the transmission and differential seals, filter, and added new fluid (no, I never changed it and I don't know if the previous owner did). They also put in new spark plugs and tie rod ends.

As soon as I got it back I noticed it was shifting weird and the engine revs much harder than normal. The most concrete description I can give is when slowly accelerating, it hits 2000 rpm at just under 20 mph, revs noisily up to about 2500 with no acceleration, then switches gears with a slight jerk and settles back to 2000. I checked the fluid level and it was overfilled. I thought that was the problem, but they sucked out the excess, adjusted the throttle and checked for vacuum leaks, all to no avail. I'm also getting 10 mpg or less, down from my usual 20ish. Any advice?