And what to do next ??

I'll tell you the story as I have recently lost my IPhone 5 ios 8.1.3, first lost my iPhone, it took 3:00 agony and torment at the computer with the expectation that the phone appear online and will show where it is, suddenly comes a message to mail, with apple account: "your Password successfully reset "and the phone propodaet of iCloud, documents and a box for me, I decided to find out how this could happen in the end I go https://appleid.apple.com/ and it says" Reset Password "and press enter ID , I enter a message arrives on the email, all became clear just guess a 4-digit password on the phone, finally gained access to e-mail, and dropped my ID, I do not understand what happened to check on ?? And what to do next ??