I am sorry to hear about the difficult circumstances surrounding your resignation. Your manager's behavior (i.e., escorting your out of the building) seemed unnecessary and insensitive, but it was not illegal.
Were you paid for your overtime? If not, then you may have a claim for unpaid overtime under the federal Fair Labor Standards Act (FLSA). There are numerous factors that would need to be considered to determine whether you have a valid overtime claim, so I would encourage you to consult with an employment attorney to get a careful evaluation.
My answers to questions posted on AVVO are intended to provide general information only, and are not intended to be legal advice. Employment law issues typically require a careful case-by-case analysis. Consequently, if you feel that you need legal advice, I would encourage you to consult in person with an employment attorney in your area.
Based on the facts provided, no there is nothing for you to file suit for.
Escorting you out of the office when your employment ends is standard practice regardless of who made the decision to terminate employment.