Oh it should have been turned upside down. open and laying on a towel w/ the screen dangling over the edge.
"Acetone, water, isopropyl, palmitate, panthenol, benzophenone-1, citric acid alcohol, denat, ethyl Esther of hydrolized silk, parfum, butylphenyl, methylpropional, hexyl cinnamal, benzyl salicylate, linalool, hydroxy-citronellal, limonene, hydroxyisohexyl, 3-cyclohexene carboxaldehyde, alpha-isomethyl ionone, citronellol, benzyl alcohol, geraniol, denatonium benzoate, benzyl cinnamate, benzyl benzoate, d&c red no. 33."
Yikes!
So, It will make it easier to help you w/ your problem to know know more information about your computer; size, exact year built
The reason I need to know that is that is so I can determine the exact layout of your MBP.
The water would be the most damaging ingredient to the electronics so again don't run it for a while.
The most damaging to the keyboard would be the Acetone!
I'll do some tests but I'm pretty sure it will dissolve the membranes of the keyboard.
I'm in Oregon and it's 6:30 AM here now. You must be West of me?
"The amount spilled is a tea spoon on the mousepad"
That's actually good. There are less critical components underneath. Usually only the battery.
" and a half teaspoon on the keyboard."
That would be the most worrisome area.
Hit me back with at least the model, size and year. We'll need to let it dry out for a while before we can do any tests, so do the towel thing.
Here's the battery disconnect on the late 2011 13":
https://www.ifixit.com/Guide/MacBook+Pro+13-Inch+Unibody+Late+2011+Battery+Repla cement/7649
getting the bottom off will help dry it out. Take the bottom off (That's actually very easy if you have or can buy a small screwdriver) and you can smell the inside and get an idea of how much got in there.
So more info and we'll go from there.