Getting back to our regularly scheduled program, yes, the symptoms you describe are perfectly in line with soaking your accessory belt. Whether or not that was the extent of the issue will reveal itself in the next few days however if it were my truck, I'd chalk it up to the splashing and move on. If it happens again soon, especially in the dry weather, then you know it's something else! As mentioned, it would be a good idea to remove the belt and make sure everything spins freely and it wasn't a failing accessory dragging the belt down, just to be on the safe side, but I think you're probably all set.

Edit: And now I see this post is over a month old... I guess the problem went away