Can this theme get hacked? lost all my traffic in one day!

I'm really confused: A few days ago I was getting from 50 - 200 uniques a day and all my pages were being indexed in google. The last few day I am getting zero, the header.php file doesn't have the Google meta tag in it anymore and I can't even find a </head> in there either. It looks like my whole blog has been hijacked cause it actually shows up inside another website! Beyond scary. I have no idea whats gone wrong. Any Ideas?

What steps should I take to get my site back...I can type the name of my site into google, and it will now only show a post or two, and to view my posts it is through someone else's domain. If I click on another it comes up as my theme, my post content, but the ads and widgets from another site not belonging to me.



Any help is appreciated!