Can i sue the guy who runs the hotel i work for?

First, are you hourly or exempt? Second, do you have a record of these times. You need something in writing. Get copies of all the records of overtime and call the wage and hour division of the department of labor, State of Iowa and you can file a complaint for up to $5,000 for the lost wages. If over $5,000 you should immediately contact an employment lawyer to get a free consult.

You may not be able to sue the supervisor who's responsible for this situation, because he may not count as an employer under federal overtime law, but you could try to make a claim against the hotel, which will almost certainly be considered your employer. This sounds like an off-the-clock case, in which the employer has hourly workers laboring for free while clocked out at the beginning or end of their shift. To counter the edits to your submitted time, I'd start copying or taking a picture of whatever paper or electronic form you complete to submit your hours so that you can show they were changed afterwards. You should also speak with an attorney who handles overtime law matters to have your situation fully and properly analyzed.

To add to Mr. Mormann's answer, even if your employer classifies you as exempt, that does not necessarily mean you are not entitled to overtime. Many employers try to avoid paying overtime by classifying employees incorrectly. It certainly would be worth a telephone call to an employment law attorney in your area.