Interaction design: Microsoft Word shows strange symbols when pressing enter

I was writing a text for my thesis and everything was going well.

Suddenly, while writing, I pressed something (I don't know what it was) and started to get strange symbols when I pressed neter or shift enter.

The characters look like this:

enter the description of the image here

I don't know what to do since the deadline is approaching.

I tried to press all the possible combinations that I could have pressed by accident, but
everything remains the same