Augh stuff like that is honestly the worst! To be honest thought it makes me think of how I often draw myself left handed even though I'm a right-y so I'm constantly either having to go back and redraw something or flipping the image to correct it
It's most common when I'm doing character illustrations like these:
But I've been guilty of overlooking such error in comics as well like here:
I want to say I'm getting better but honestly unless I'm checking and double checking I end up totally missing mistakes like that