> Are there any other teens going on this cruise? I am 19 and
> have a twin sister
CruiseMates has a fairly large group onboard this sailing. Within that group there are a number of kids ranging from 12-25, I think. My own sons, 15 and 20 will be with us.
Being a holiday cruise, I'm sure there will lots of teens onboard. You shouldn't have any problems meeting many in your age range.