black screen minimizing itself

I've never had a problem like this before and it's really weird.

So today I opened up to launcher to play the game, clicked 'play' and then the launcher window closed like it always does, and then the screen went black as usual before the game started to load. However, instead of loading and the sims logo appearing on the screen, it stayed black, and then the window minimized itself. When I clicked on the icon on the taskbar to re-open it, it stayed on for a few seconds (still black) and then minimized itself again. The game still loads because after a while I can hear the music on the main menu, but only for a few seconds because then the window minimizes itself again. I tried starting it in the windowed mode and it worked. There was no black screen and the window stayed opened. Or course, I don't want to play this way all the time. How can I fix this? How I can I get it to stay in fullscreen mode without going black and minimizing itself?