Hi, Amanda. I too used to have a small headset icon on the upper left side of the phone. I was under the impression that it was there because I was using my headphones, but apparently not, because I have my headphones on at night and as we speak and there's no icon.
advice would be to wait a week or two, and see what happens. That's about how long it took mine to go away finally. I wish I could be more help.
Anyway, please keep me posted, and good luck. Take care.