Looking at your comic, simple backgrounds actually work well for the style and subject material, IMO.
For more story-driven things, backgrounds can be really important to set a scene, a location, a mood. But in episodic slice-of-life type things like yours, backgrounds honestly aren't that important for the most part.
My advice: don't worry too much on making the backgrounds detailed or impressive since they are not the focus of your comic. If their function is just to minimally establish a setting, you will be surprised how far a handful of well-placed lines can go.
For future / other projects you may do, I'd say (a) learn the basics of perspective if you haven't already, (b) use references, (c) what Dawg said - big picture first, details later, and (d) practice. 