when free flight training back fires

[GlassOnion]

You've taken her to the vet for a FULL blood panel and fecal swab recently?

[Shelby]

Sorry for the confusion. No, she bites at other times, like when she is on the cage or when I want her to set up and she doesn't listen, so I grab her foot and make her step up.

Sounds to me like sometimes she's getting fed up with you. Birds don't like to be forced to do something; you have to make them think it was their idea. Also, pay very close attention to her body language. You may be able to avoid bites if can you see she's getting ticked off and can get out of the way, or stop doing what is making her mad in time.

After eliminating any possible medical reasons for her behavior, go read these very basic taming/targeting articles and put them to use:
http://trainedparrot.com/Taming/
http://theparrotforum.com/viewtopic.php?f=11&t=227
Clicker Training Made Easy (video)
You may have to "go back to the beginning" in order to make forward progress. Make sure she associates you with good experiences!

Also, keep in mind that (depending on where you live) it is breeding season right now, so she's going to be more hormonal, moody, and aggressive than usual. Good luck and keep us updated!