Looking for suggestions on what to do (Falmouth)

I'll be on my own (didn't want to do what my friends are doing) in Falmouth during a cruise stop on Carnival. I'd love to do some water activities like snorkeling/swimming with dolphins, but all of the ones offered by my cruiseline combo it with climbing the waterfall, which I do not want to do. The other excursions like historical tours or zip lining don't interest me either (would rather not do something I can do back in the states easily).

This is also my first time cruising (and first time in Jamaica), and since I'm by myself, I'm a bit hesitant to take a cab to somewhere nearby, due to safety reasons and stories about not getting back to the boat in time. I found a food tour that lasts about 3 hours, but I'll still be there for about 3-4 hours before boarding. I noticed that the port itself doesn't have a nice beach, so what are some recommendations for what to do?

I'm starting to think that this port is just not right for me, and that maybe I should just find some Rasta guy and just chill out for a few hours? Any suggestions are appreciated!

We did the Catamaran snorkel tour and it was wonderful! We were docked in Falmouth and took a bus to Montego Bay. We booked through the Royal Carib. ship we were on