one monitor two screens

I hope this makes some kind of sense to you.
Occasionally when I use remote access I end up with a totally black screen on my pc. (I access my pc from my smart phone)
Today after using a remote connection I found that my pc screen was totally black with two post it notes in the corner. My browser was sticking out from the edge and I managed to pull it so now it is on the screen. My background picture has reappeared but none of the shortcuts is there nor the taskbar.
If I go back to my phone and remote in, i can see my screen as it should look. All the shortcuts are there, the task bar and the browser(s).
As I said, this has happened twice before and I managed to fix it. But I cannot remember how. It took days.
I hope that you can help me. please use very plain language.
ty
Janice

If you are in the Metro Screen, it is most likely a technical glitch. What are you using for Remote Connection? I have never had any problems using Team Viewer. Even though a Smartphone makes it really hard to tell what you are doing.