Being yourself around everyone is easier said than done, but the more you can do it, the happier you will be. Getting older naturally makes it easier for most people. That's part of the reason older people are happier.
I've never quite understood the appeal of ren faires, mainly because I'm frugal and I always felt like there wasn't much to do except buy stuff. Reading your comment, I think there might be a key step or two that I overlooked.
Sometimes it's good to care. If someone is saying you're acts are immoral irresponsible or genuinely with your interests in mind you should listen and make a decision. If its someone saying you're being odd or being weird they're projecting their own self consciousness to stand out from the crowd.