Do you get paid what you should?

My question is does your company pay you what they agreed to pay you, because mine doesn't. About two months ago my boss said there were all these unused hours on the contract my team works on and that if anyone could help make up these hours they would be compensated. After asking what the compensation was my boss finally said for the extra time you work you will be paid at whatever the hourly rate of your salary is.

For the last month and a half, I've been putting lots of extra hours and my boss hasn't compensated me AT ALL. NOT EVEN A F@CKING THANK YOU. So I talked to her about this and she claims she never said the company would compensate us (me), which is the biggest load of sh!t I've ever heard.

I Really need advice, what do you think I should do?