Double click units

I'm not sure if this is a bug or just slow so I thought discussion forum rather than bug. I noticed when trying to just build two units I double click and for some strange reason it adds three....has anyone else noticed that? It's like the game didn't register the first click or soemthing and I double upped it.

Yea it happens when you double click fast don't know if its bug or not

You might just want to hold the + button, not click it repeatedly.