I had a little light-headedness, but the one thing I wish I had thought about before I had my first shower was to arrange things differently than the way I usually have my shower implements.
By that I mean my back was to the spray of water to minimize hard stream of water on my incisions, but my soap, washcloth, shampoo and conditioner were all in a caddy under the shower head. I hadn't realized I couldn't have my feet planted one way and just twist around the opposite way to reach those items - OW! So I had to slowly turn around and reach up each time for each item. It would have been much better to have those goodies within reach in front of me, rather than behind.
I did have to use the walls to balance myself several times. It is slowly getting better.