Found on the internet does not equate to being in the public domain. You can't make it write by weaseling disclaimers saying you stole the work.
US laws are however is not likely to affect you in Croatia. They'd have to sue you there. Croatia is a signatory to the Berne Copyright Convention (Treaty) so their US Copyright is enforceable in Croatia. Of course, they can (and probably already have) complained to your ISP and are working at getting your site (at least the parts with the images you STOLE from them) knocked down. Since BLUEHOST appears to be a US hosting site, they will almost certainly respond to any requests from the property owner and get rid of the content in order to avoid getting SUED themselves. (It appears BLUEHOST has already taken your site down.....
We can't help you with your Croatian legal issues, this is US law forum only. I do recommend that you take down the images you STOLE form other sites and not use material you do not have permission to post.