I DON'T KNOW WHAT HAPPENED!!

I went to see if I could change my avatar picture and it erased it alltogether! I don't get it. And I can't get the avatar back! Does anyone know how to get that picture back? I'm all forklemp!! Please someone help me!! My before picture was my chat avatar and now it's gone. It's still on my profile, but I want people to be able to see it when I post! Jen Halliday