My proyect only sounds in one side

Post screenshot entire UI with clip expanded vertically.

Check the file in the bin ... right-click, and check for audio channels. You can also go into the sequence settings and check your channel setup.

And make sure you haven't done something like accidentally changing something in the Audio Track mixer, which happens at times, as there are keyboard shortcuts for some things you might have accidentally blipped while playing the file.

Does it sound in stereo if you play the clip in the source monitor?