Know the feeling Helmut. Been with Her Majesty's finest for nearly 4 years now. I wouldn't worry to much about having time to play, as you should get a fair amount of time off when you do a run ashore. But then again I can imagine you will be enjoying the 'sights'
http://uk.youtube.com/watch?v=EtOMl6mFGR0 << Third guy has the the idea of real 'Shore' Leave. (Language might be unsuitable if kids are around)