Sunburned belly button :( What to wear?!

This is probably the strangest problem youve ever heard of, but here goes. I went hiking with my friends yesterday and I wore a short shirt. I made sure to put sunscreen all over my back and stomach but somehow I missed my belly button and it got sunburned really bad! Youre probably wondering how my belly button got sunburned, and its because I have a big stick-out one since I had a hernia as a baby which closed up but never went in at all. When I was little it was like a golf ball and it got a little smaller thru my teenage years but its still about an inch long.

So now I have this big ball of sunburned skin sticking out from my belly and I can't figure out what to wear so it won't hurt all day! Ive tried both loose and tight shirts but either way my belly button rubs against it when I walk or stretch so by the end of the day it is completely raw and even the slightest touch hurts like hell. And I don't wanna wear shirts that end above my belly button because it looks like I have a big cherry sticking out from my stomach!

So does anyone have any ideas how I can stop this madness?