Zoo: Platypus @ISO3200

Questionable choice, I suppose. But I've always wanted a photo of a platypus. And since I respected the sign in their very ill-lit area (unlike some visitors I saw that day), I did not use a flash. Instead, I used my 17-50mm lens at ISO3200, f3.5 (max on the lens) at (if I recall correctly) 1/8 second, panning. Hand-held, 'cause the animals don't swim in a straight line all the time (also, they never seem to stop moving!).
Then I went home (actually, I went to the gorilla enclosure and kept shooting, but you know what I mean), cropped and did some levels and brightness adjustments in photoshop.
Advice/feedback?
Then I went home (actually, I went to the gorilla enclosure and kept shooting, but you know what I mean), cropped and did some levels and brightness adjustments in photoshop.

Advice/feedback?