They said it was a joke because they'd never seen anything like it before. It's unusual, different, and original. That's the direction you should always go. Always go with your gut, even if there's a voice in your head telling you it's stupid, or an outsider's voice telling you it's stupid. Don't stand for it. Take the risk and always make that your purpose. You have a natural instinct.
It's hard sometimes when people criticize our work in such a crappy and needlessly mean way, but the thing to remember is in the end what truly matters is how YOU feel about your work and how YOU feel when creating it. If making it makes you happy, or fulfilled, or zen, or whatever emotion creation fills you with, that's far more important than what others think of it. Make the art YOU want to make, and to hell with what others think!
I'm so sorry that happened to you. I think lots of us take our work very personally, at least I do. Maybe non-artistic types don't realize how much of ourselves we put into everything we do. It would take me a long time to be able to paint with the creativity that you do and I admire that ability so much!
Back in the early 1980s I attempted some rather tame experimental abstract photographs in color. Oregon at that time was not the progressive state it is now, and photographers as a group tend to be quite provincial to begin with (then and now). Color — any color — wasn’t yet universally accepted as photographic art. People expected to see black-and-white landscapes, and especially wanted to see Ansel Adams-style black-and-white landscapes.
In that environment, these new pictures were haughtily decreed to be “not REAL photography”, and therefore wouldn’t be shown in any of the few galleries which at that time would feature photography. That reception caused me to abandon color and abstraction completely for several decades.
Don’t get me wrong; I’m very happy with the B&W work I’ve done over the years (and I don't do landscapes!) But I do regret allowing the closed-mindedness of a few people to affect the art that I made. It won't happen again.