Heading to CSS next week for our first Caribbean trip... How do you "do" a resort?

This is my first time going on any type of luxury trip, my girlfriend and I are both about 30 and will be there for a full week starting Tuesday. We're both really excited, but my last trip was a ski trip in Colorado that went poorly and I'm trying to avoid a repeat situation.

I know most of the basic on site amenities like the gym and the water sports area, but what's the vibe apart from that? Is there a lot "going on" or is it a self-paced week of drinking and relaxing in the sun? Any general tips on how to make the most of things while we're there? Any "surprises" to look out for like "oh the all-inclusive is for house liquor but if you order a patron margarita you'll get billed?" We were told by our agent not to worry about tipping, is that still true?