The only thing I did was to get an dedicated ip on the 28 november, in wich day there was less visitors as for some strange reason, some visitor got another website, but that was ok the day after.
This might be a possible cause... certainly one to be checked over. I've never had a glitch as you described after making a dns change, where the visitor has gotten the wrong domain. Conceivably, not everything was done properly when you made your change, or there was some problem at the host.
While Google's index is domain-based, not IP-based, the change in IP might have also caused Google to re-evaluate geo-location, or at least to restart the evaluation process.
There are several possible factors affecting geo-location at work here. Host location, inbound links, and language are three large factors that Google looks at wrt international geo-location. TLD is another. They are all interdependent. So, if linking and language signals are sufficiently strong, hosting location might not be a significant factor at all.
English is most likely more competitive than Spanish and Swedish. If your host is physically in Spain, is it possible that your inbound links, even when in English, are predominantly from Spain?
As I understand it, you have one domain for all of your languages, with separate directories for each language. Is it a top level tld (.com, .net)? Can you describe your setup in a little more detail.
I have not done any changes to the website, as I said, the 3 index pages are copies, only the language differ, and only main homepage fallen.
If the languages are different, this will not be considered duplicate content, so don't be concerned about that.