Do I have a DNS problem?

I am a free user. I want to load my domain, hmtown.com, with simple HTML. I have tried to use github.com but somehow my small repo is busy. I tried specifying a small directory on my computer. Something said it worked but the "working URL" was not related to hmtown.com and it didn't work when I clicked on it?
Do I have a DNS problem? Is my problem related to my free account?