based on what you have shared this does not seem to meet the criteria of a emergency. er care is very expensive and a child with gum problems would not likely be seen promptly since the more critical cases will be seen first. since she is apparently not in pain (you didn't mention this) i think you will wait until tomorrow but of course the choice is yours. she really needs to see a dentist and most will see a child the same day if they can or at least refer you to a dental facility that will.
should i take my 4 yr old to the er to have her gums looked at. . she told me fri. night that her gums hurt so i peeked in and there was a hole in her gums just above where the lip meets the gums. so i made some salt water and had her rinse. since it was the weekend i can't get an appt. so i will call to make an appt. on mon ( but i am unsure if i could even get an appt that day. or that week. ) i've been checking it and her gums around her teeth seems to be getting inflamed. help pls.