OS crash report

i received an error message stating that.Due to a third party application, your operating system is crashed. Contact Support for Immediate Fix. 1-866-777-6226. I very foolishly called and gave my name and email address. The guy connected remotely to my computer! I have never done anything like this before. I shut everything down after 2 minutes and disconnected from the Internet. I called my internet provider who gave me a new IP address, but I still can't get Safari to work.