Neither of them are full sentences or questions so you need more words and no question mark. You needed the question mark after "What's the difference here".
In BrE, "your holiday(s)" means any period of time when you are on holiday/leave from work or school and are travelling somewhere for leisure purposes.
Sarah - I can't wait for the school holidays.
Peter - Me neither. Are you going on holiday?
Sarah - Yes. We're spending our holiday in LA!
Peter - You lucky thing. We're just going on holiday to Bognor Regis.
As you can see, there are three uses/forms of "holiday" in that exchange.