I want to go on a school trip to Belgium but I might be too homesick? Any tips?

It would take a really long time to get there and we'd have to go on a ferry overnight. I am not very good at being away from home but I don't want to miss out on this opportunity. It's with my history cl and we'd be away for six nights. I'm a nervous and private person so I don't know if I'd be able to stay away from home for so long with other people. Does anyone have any good tips about how to overcome fears of going away and just get on with it?