The criticism is of the thing you built, not you. It's hard to separate those things, but you have to try to keep that in mind. I've built lots of things that were cool to me, but not to others, and that's ok.

There is a saying, no product survives first contact with customers. You state you finished it, but we all know that software is never complete.

You need to get over the fear and not tie the reception of your product to your personal perspective of self worth. The reception of your product is not a reflection of you.

More important than the initial release is how you receive feedback and criticism, and then adjust your product.

Will you laugh last... that's the question. I know it's easy to give the answers I've given and harder to publish; I'm wrestling with similar things myself. But the chances of real infamy are remarkably small; you're far more likely to be hit by a bus, which would be worse.

There are folks who will always criticize something. You're going to have to deal with that, regardless of what you do. But if you have valid counters to the criticism then use those to try to educate your detractors (and others).