Sorry you burned your arm, Laura, I hope it feels better soon and heals fast.
But you shouldn't call yourself stupid, ok? The book I'm reading, called "How to make yourself happy: and remarkably less disturbable", says there are no stupid people, only stupid things. So you aren't stupid for burning your arm, you just did a stupid thing. It's not your fault, per se, because people will always do stupid things from time to time. So take heart, you're just like everyone else in that respect!
Take care,
Brenda