Please help if you can :S

Hi yesterday a guy called Ronen Ayash tried to scam me and he did it we were suppose to trade accs he wanted a CA account and i wanted steam acc with COD MODERN WARFARE he said we will trade he gave me info and stuff i changed the e-mail the secret question and the password and then i gave him my account and he changed the password so now i logged in at the moment its 4:52 AM and i wanted to log in on steam and i see the password IS CHANGED! and i have a password change code in my Inbox on hotmail but i dont know the secret question he changed it it was the question Where were you born so for me it was BITOLA my main city and then i typed the code and the secret question IT SAYS THERE IS A PROBLEM please help me guys! i dont wanna get scammed to this shit guy... AND HOW WAS HE ABLE TO CHANGE THE PASS EVEN IF I CHANGED MY WHOLE INFO?!