Change in print bed after printing ABS

Hi everyone, after doing my first print in ABS, I noticed that the print surface had gotten some brown spots on it, and there are these white “stains” all accross the bed’s edges. Is this normal, or should I be worrying about this?

Not sure about the darker spots, but the lighter areas clearly depicted in the 2nd image are air bubbles between the glass and the PEI sheet. You can probably push them around with your fingernail. They don’t seem to be a big deal (and pretty normal/common) as long as they stay like that, but I’ve seen pics of some that have formed large air bubbles (like several inches) which will make the PEI sheet no longer flat. They change with the heat as well.