Play screen wont open

I am logged in to Minecraft, however, when I click play, it brings me to a game output screen.

What I expected to happen was...:
My normal play screen would open.

What actually happened was...:
A blank white screen with a play button at the bottom, that does not work, The tab on the screen is labeled "game output".

Steps to Reproduce:
1. Click on Minecraft ;auncher link on my home screen.
2. Click play
3. Brings me to "game output" screen and I can't do anything else.