Mommies, at what point would you go to the er?

ok this is actually about me not my kids, but mommies always seem to have the best advice. thiss past saturday we went on a family outing to an airshow. i didn't wear sunscreen (stupid i know), but now i have sun poisoning. i've done research on it. i've tried almost every home remeddy i can find on the internet, aloe, cool baths, hot bathes. NOTHING is working. the sting of the burn itself has gone away for the most part, but the probelm i'm having now is that the swelling in my legs is so bad, that if i stand up for longer than a cople of minutes, i'm in so much pain i'm in tears. as any mommy know i REALLY dont have time for this. but it doesnt show any signs of letting up, and its been like this since saturday when we got home. at what point should i give in and go to the er? we currently dont have a family dr. i'm 23+4 days pregnant if that matters..