With one post you won't get anywhere, you need to put some more effort. I have my own community, which is quite a bit more niche than yours, but by posting everyday it has been growing slowly.
Yours has lots of potential but needs more people to find it. Most people find a community from a post and people tend to look at newer posts, so you have to put something out regularly.

I'm in the same situation, I've made m/rhythmgames with also 3 subscribers, no responses yet but still better than being on reddit!