Wow, you did well, congrats. I've never known anyone to win serious money with those sites.
Can I absolutely guarantee that nothing bad will happen-of course not. However, there are no laws, either federal or state, that prohibit what you are doing at this point and time, so the chance of something happening is very, very, very, remote. The U.S. government isn't interested in the small time players sitting at their computers placing bets, but at the operators of the companies themselves; in fact, there are some sites that no longer accept players from the U.S. thanks in no small part to the pressure exerted by the federal government.
You may want to consult with a tax lawyer or accountant about those winnings, since you may have to report the earnings as taxable income next year.
Good luck to you. If you have any additional questions, please press the reply button, and I will be happy to assist you further.
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