I would like to now if I am using the prepositions correctly:
"She was not pleased with her job and was tired of doing the same thing every day, but everybody was surprised at her attitude"
I always confuse them.
"Pleased with" and "tired of" are unambiguously correct.
"Surprised at" is also correct, but in American English it sounds a little clunky. In a sentence like yours above, I would usually choose "by": "...but everybody was surprised by her attitude."
One weird quirk with the word "surprised" is the change in meaning when the object of the preposition is a person. Consider:
Julie was surprised by Samantha.
This indicates that Samantha surprised Julie on purpose somehow, like by hiding behind the curtains for a surprise party, or sending her an unexpected gift.
Julie was surprised at Samantha.
This indicates that Samantha behaved in a way that Julie hadn't anticipated. Samantha wasn't behaving with Julie in mind; she just acted, but her behavior surprised Julie.
That is just a weird distinction with people, though. For the most part, you can use "at" and "by" interchangeably with "surprised" and people will get your meaning without much trouble.