Job Offer

Got my job offer today and signed it - now I am officially owned for four months. The idea of an employment contract scares me - even after taking law class. Surely, a contract has to have an offer and an acceptance, also consideration. So I see the breakdown as follow:

Offer - "Here's a job for you and we will pay you"
Acceptance - "I will take the job"
Consideration - "I have to work for them"

Unfortunately, nobody dictates the amount of consideration in a contract. As long as there is SOME consideration. So literally, they can work me like a dog and pay me minimum wage.. wait, that sounds like co-op. :) So my fear is justified.