It will not let me play the game whenever I click on "Play."

It will not let me play the game whenever I click on "Play."
What I expected to happen was...:
I expected it to let me go on and play the game when I log in.
What actually happened was...:
It does load up and let me play the game
Steps to Reproduce:
1. Click on Minecraft
2. Click on "Play" to play the game.
3. It loads and gives me a crash report and tells me to report to Mojang.