J.T.
Whether you are exempt vs. non-exempt should be made clear to you at the time you are hired. Typically expemt personeel are salaried and non-exempt are hourly.
I would call the HR department and ask if the position is exempt or non-exempt and what their position is on overtime. After you speak with them, you can then call your loacl DoL and find out if what they are doing is legal.
For example, one company I worked for if you were salaried exepmt you did not get overtime unless you worked more than five hours over AND had approval from you supervisor prior to working the hours. Then, you did not get time and a half, onlly whatever your hourly rate would out to.