Leave Me Alone Please!

My son, Seamus, has started taking showers on his own a few days ago. He loves it! He feels free and in charge. The day it started was, let's just say hysterical and a little bit of empty nest syndrome. I turned the water on and told Seamus to get in. He did and immediately washed his hair. 15 minutes later I thought to myself; Wow this kid is taking a long time... So I venture in and pop my head in the shower.  "Seamus, grab the soap and was your body.", Seamus grabs the soap, "Okay mommy, can you please leave now?". I was crushed but I thought it was hilarious. Here my four year old son is grown enough to kick his own mother out of the shower and demand privacy! I didn't take it to heart, I knew my little boy was turning into my little man.