I know that is my fault, but what i am asking is :
Am i safe with google authenticator ,or should i just do something else, i normally don't think any better way to protect my account then a google authenticator code that changes every 30 seconds in my phone , or is there something better ?
You should be safe with the Google Authenticator, but I highly recommend that you change your Blockchain.info password and on every website where you use this password as well.
He should be safe but you should never solely rely on these things. I'd also scan your computer for malware and make sure you don't have a keylogger first, because if you do changing your password wont do much good as they'll immediately know it.