Baby's head is sunburned - (Mom Guilt is Strong) 😟

I took my (fairly bald) baby out to an Easter Egg Hunt today but she was only out in the sun/overcast for about 15 minutes. (I now know that's all it takes! 😣) She didn't have sunscreen on. I had a hat and sunglasses for her but didn't put them on - like an idiot. She is 9 months this week. My mom guilt is so strong right now! This is our first time going out in the sun like this. Thankfully, her head is only slightly burned so far. It's not warm to the touch, she's been acting fine and her diapers are still very wet. What should I do? Should it be treated with anything? Aloe?

Ugh! I literally feel like the worst Mom. I know for next time but still!