Going into shed.. But shows a cut on the belly.. laying in water.. Help

Yes I am running an uth without tstat at the moment but I was already told to get one so I directly ordered one.

Bought a thermometer and a dim switch so I can at least keep the temparature right until I get the tstat and thermometer/hygrometer.

It says 89F inside his hide and 79f on the cool side at the moment.

So glad I stumbled on this thread! I had noticed a very similar cut on my ball python today and the pictures from the OP look almost exactly like the one on my 7 week old ball python. Good to know it's just from the umbilical! I have been trying to keep the humidity up because mine is also "in blue" and was worried that I'd upped the humidity TOO much and she was showing the beginnings of scale rot! Everything else on her looks fantastic though so this thread definitely eases my worries :). Gotta love being overprotective pet moms and dads haha! :p