If your friend can demonstrate that she was on medication that would prevent her from understanding the nature of the plea agreement that she signed or her righst regarding her case, she should be able to get her plea back or, if the judge denies that, to reverse her conviction on appeal. Similarly, if she was denied the medication she needed in order to understand the nature of the proceedings against her the same outcome would apply.
If there's an issue as to her mental competency that needs to be evaluated and if she's incompetent, the plea cannot stand.
Self-defense is an affirmative defense. That is, it has to be proved by the defendant at trial. If she can do that, it's a complete defense. She chose not to do that and the issue is whether she understood any of the choices she had.
Lawyers on this site merely provide general legal information, because JustAnswer is not a law firm and that is all we are allowed to do on a site such as this. We cannot represent your friend. The terms of service on the site do not allow us to even refer customers to specific attorneys or law firms.
What I can do, however, is to refer you to one of the same services that lawyers themselves use when they need to consult with an out of town attorney or an attorney in a different subspecialty and don't know of anyone personally.
You can find a new criminal lawyer by looking at the California Bar Association's Lawyer Referral Service or a commercial service like Martindale.com. For a very modest referral fee they will find you a lawyer.
Martindale's lawyers are peer and colleague rated, which some find useful to help narrow down the options.