Right phrases, wrong order....
"Please bring me a beer."
"Thank You"
"Hello"
I felt the same when I was stationed in Panama (even though I had taken Spanish for two years in high school). Each country has different slang and when they speak really fast, I can only pick up a word or two. Like Jenn said, you'll pick it up as your stay lengthens.
Dude, I took Spanish for 10 years and I still can't speak very much of it. LOL!!!