Am I a bitch?

So my SO and I are in Hawaii with his family on a vacation. We made tentative plans before we left on what we were going to be doing. The first day we got here was my birthday. I wanted to snorkel for it. We did not. We are over half way through our trip and have done nothing that my SO and I have wanted to do. There is a specific beach I want to go to because the chance of seeing turtles is high. They don't want to go. So basically anything we want to do gets pushed back and I know won't get done. So I am to the point that I told my SO to rent our own car for the rest of the week. Everything so far has been about what his brother wants to do and I am starting to get irritated. Well me SO is now mad at me and won't explain why. Am I a bitch? We paid a lot of money to get here and probably won't be coming back for quite a while, if we do. I think it's fair we get to do stuff we want to do. What do you think?