FUCKING HACKERS!

yesterday i donwloaded origin(I dont know it is the problam in it) and my steam was closed. When i tried to run the steam i get the login vindom where i can put only mi nick and password i cannot turn it off or canncel logining(i have set auto login in steam)... So i enter my nick and password and i succesful login to steame.Today i get 2letters to my gmail accout:
First from Google team:

Arnas!

Someone recently tried to log in with your Google Account ( xxxxxxxxxxxxxxxx ). Did not allow to connect, as it could be hijacker trying to access your account. View detailed test log information:

In 2012. 21 June. Thursday 17:24:13 GMT
IP Address: 99.9.196.100 ( sbcglobal.net )
Location: Trophy Club, Texas, United States of America

If you attempt to connect you to the unknown, it may be that someone else is trying to access your account. You should immediately log in to your account and reset your password. Learn how to do this by visiting the following address: http://support.google.com/accounts?p=reset_pm

Respectfully
Google Accounts Team

Second from steam:

Dear arnas1581,

We've received a request to access your Steam account from a new computer
or web browser.
To complete this process, enter the following special access code into the
authorization dialog before trying to log in again:

xxxx

If you did not attempt this action, please change your password immediately.
Thanks for helping us maintain the security of your account.
The Steam Support Team
http://www.steampowered.com

How i can harm to the person who tried to hack me???? i have only this ip addres(now you have it too :D)?
BTW i changes the securiti code and my email to xxxxxxxxx