Jeff, that walk wasn't stupid. Walking is what is gonna get all those nasties out of your bladder, so keep at it. Drink lots of water before hand, then walk. If you can find a little private spot to empty the bag during your walk, once you see the after-parts of the surgery in the bag, then drain it out on a tree root or something...lol People will think you are just tieing your shoelace.
Don't let that junk spook you, its good to get the gunk out...makes healing much easier. Walking or other purposeful activities will give you a sense of purpose and help with the depression. Sitting in the chair and moaning just makes it worse, so I found out, when I had my post-surgery bout of it.