Ooo! Steam burns are miserable. You're going to feel pain for a good bit of time, at least tonight. Keep it cool water or use a cool cloth on it--not ice. The webmd site says you might benefit from taking ibuprofin or tylenol too.
burns suck and really hurt for awhile! for future reference or if you're still in pain, there is this amazing pain relieving stuff called "Dermaplast" (i *think* that's the name) - it totally cools it and relieves the pain. it's a spray and it really helps soothe and cool it down. it is so good that hospitals give it to moms after childbirth to spray on their stitches after episiotomies (but it says on the sprayer that it's for burns)! i took it home and used it for like a week after i gave birth - it is that good. now i always make sure i have some on hand in case anyone in our house gets a burn or something. i love this stuff!
I got something at Walgreens when I was dumb and put my hand on the still hot coils of my stovetop. It seemed to help me heal and take away the pain. I can't remember the name but the pharmacist was the one to tell me about it.