Trans Snafu and ???

Hey all!
Well here's the quick story... I did a burn out the other day, Thought nothing of it. DROVE the car back into the garage and parked it. Today I went to move it and NOTHING.. No Forward, No reverse... Of course checked the linkage (ok) Fluid is slightly over filled, not burnt. The trans is a 904 that was "gone thru before install" and has a manual reverse pattern valve body, stock internals.

What did I Break ???

Thing that's confuzing me the most is .. I Drove it into the garage!