Mine craft not working? every time I click on the minecraft.exe link it doesn't work.?

i go to the website and click download, when i click on the download for windows (minecraft.exe) it starts the launcher and when i log in another screen pops up. The screen shows the loading bar for a split second and than the screen goes black and doesn't do anything else. i have waited for 30 minutes and still nothing happens. I've played mine craft on this laptop before today without any problems, but then around 5:30 when i tried it this thing happened, and everytime i try it happens again. i have tried both links also.