Hi there! Looks like you linked to a Lemmy community using a URL instead of its name, which doesn't work well for people on different instances. Try fixing it like this: !lemmytellusomething@lemmy.world
No, you're correct. The software was named after the small rodent (lemming). One of the co-creators of lemmy talks about the name here: https://lemmy.ml/post/70319
It's just that "lemmy" sounds like you're saying "let me" quickly and not enunciating properly.