I put synthetic tranny oil in (full change

), a few weeks ago, and initially, the shifts took more effort, but it got better and better (less effort and 'lag').
However, it seems that when I shift, things are hitting each other inside the tranny. For example, on a slow, 1/4 throttle upshift from 2nd to 3rd, I got a quiet 'bang' (or metal on metal 'thud') from something hitting. This was a slow, lazy shift. Also, I am 'feeling' some grinding when I shift, like someone was trying to put the car in gear with the clutch out (not that I have done that...seriously!)
What the hell is going on? This car has 95k miles and things better not be giving up now!