Yeah, I was worried that might happen. It disoriented me a few times but I thought it was just me. Thank you for your feedback, I'll see if I can fix it.
a good way to make the background is to make a tilemap. It's the thing they use in rpg's and the early Pokemon games where instead of drawing one big map, you draw lots of tiny little squares and join them together to make a much more detailed background. It would also stop the inconsistent pixel size which i'm guessing wasn't a design decision of yours.