International Plan

Hi. Before I left for my trip I purchased the international plan for $30 where I was to recieve unlimited texts and photo sharing. I also was to revive 120mb of data and $1 a minute calling. This worked well in Toronto and in Germany but when I got to Croatia i received a text that this country was not included in my plan and that I would have to pay $19.99 per MB of data. However when I spoke to the rep that sold me the plan I told her where I was going and she did not tell me this. Can anyone clarify? Thanks
Christina