Why does Safari close it's window when I press "ESC" to exit full screen?

I'm getting really disappointed with my Macbook Pro. First, it was when I pressed full screen on Youtube, it would just show a plain white rectangle with a small black rectangle on the upper left hand corner. Now, and this is on ANY website that gives you the option of showing the video full screen, the browser just hides. The video's audio is still playing but the page isn't there. It doesn't close, or "quit" completely, but when I press the Safari icon in the dock again and again and again, it doesn't even open back up! AT ALL. I have to quit Safari completely in order to open Safari back up. No, I didn't mess with any of its settings, everything is updated, and this laptop only 5 months old. There shouldn't be a problem but sadly, every 2-3 months comes a new issue.