92 QWeird problem after transmission Filter change

[bpeesy]

I have a 92Q (chain guides replaced) -- always ran great, Over this past weekend I drained the fluid & cleaned the transmission pan and screen. After putting everything back together The car has a weird problem. When I put the Car in Reverse it won't move. When I put it in Neutral, it's like its in drive. When I put it in drive it acts like it's in 2nd gear and so forth. Does anyone have any idea what could have happened & what's the remedy for this weird problem. I never had any transmission problems prior to this happening