My foot has been swollen for 3 days due to an allergic reaction. Should i go to the doctor?

3 days ago i was bitten by what i'm almost positive was a deer fly. About 45 mins after the bite, my foot was swollen. It has continued to get swell more and more I was bitten by my toe and the swelling goes up my ankle. I went to the doctor and they said after 24 hours go to the ER for an IV and meds (lots of help, i know!). I'm wondering if anyone else has been thru this...i've soaked my foot in epsom salt, kept it elevated, applied a cold compress, and used cream on it. Just wanted to ask before i go in to the Emergency Room.