Horizontal parallel borders

Help, my cat jumped on my keyboard in the middle of my editing and threw me into some mode where there are white borders along the top and bottom. This squished the visual of the audio and also lowered the volume considerably on playback. How do I get out of this?

That’s probably two separate things.

If the “white borders” look like this:

then your cat has selected the “Multi-tool” (probably by standing on te F6 key).
Press the F1 key to get back to the normal “Selection Tool”.
More info: Multi-Tool - Audacity Manual

“Lowered the volume considerably on playback” is probably due to your cat moving the track “Gain” slider. Move it back to the center position.
See: Audio Tracks - Audacity Manual

Mine looks like this:
Screenshot from 2019-07-28 13-22-10.png

Please post a screenshot that includes the panel on the left end of the track.

Screenshot from 2019-07-28 17-28-42.png

The track is set to “Waveform (dB)” view.
To set it back to normal “Waveform” view, click on the name of the track and select “Waveform” from the dropdown menu.
(See: https://manual.audacityteam.org/man/audio_track_dropdown_menu.html)

The track is also zoomed in vertically. To zoom back out to normal, right click on the vertical scale and select “Zoom Reset”.
(See also: https://manual.audacityteam.org/man/vertical_zooming.html)

The track gain and track pan sliders are also moved to the right.
See: https://manual.audacityteam.org/man/audio_tracks.html#gain