help!

Has anyone ever given a verbal yes, but not gone thru with signing the contract?
I said yes to a contract on Friday over the phone. I got the written contract on Sat. I thought I would be getting a better rate, was told I'd be making one amount, but then found out, it's "like" i'm making that when you factor in the tax advantage. That, and my husband is having second thoughts about me traveling to NYC alone. Well, now they are saying it's too late to get anyone else, and that I made a verbal contract with them. I don't know what to do now. I'm I really obligated with the verbal contract?