View the screenshots below. It shows that I earned
Steeling with Feeling: Level up the Blacksmith BUT I did NOT earn
To The Smithy!: Acquire the Blacksmith
I am assuming that this is a glitch, or did I do something wrong?
In the first few days after the game launched, there were a multitude of achievement glitches. If your game was interrupted around the time you earned that achievement, it may not have synced properly.
The "Lore" achievements in particular were quite buggy. Blizzard has said that they're aware of the problem and are working to fix it.
From a recent forum post:
For now, sit tight, and hopefully later the glitches will be fixed and there will be some way to repair these buggy achievements.