Do you have proof that you paid the last month's rent. That will be critical in the event that you do get sued.
Beyond that, she can't kick you out or change the locks without getting a court order. But just because someone can't legally do something does not mean they won't do it anyway. I would stop taking her calls and ask her to communicate in writing only. She can show up, but is not entitled to gain entry without giving you advance written notice. It sounds like you are going to have problems with her whether you are legally in the right or not. Good luck.
She can't legally do any of those things unilaterally. If she believes she is owed rent, she can try to evict you through an unlawful detainer process, and if she succeeds and gets a writ of possession, she can then have you locked out. Generally speaking, at the end of a lease, if no new agreement is signed, the lease becomes month-to-month (although the terms of the written lease can alter this so look there first). As with most of these issues, there is no shortcut to getting legal advice and that is the only way to really answer your question but hopefully this helps.
If you have receipts you are in the right and she is just an idiot.
My name is Stephen R. Cohen and have practiced since 1974. I practice in Los Angeles and Orange County, CA. These answers do not create an attorney client relationship. My answers may offend I believe in telling the truth, I use common sense as well as the law. Other state's laws may differ.. There are a lot of really good attorneys on this site, I will do limited appearances which are preparation of court documents it is , less expensive. However generally I believe an attorney is better than none, but many will offer a free consultation and a face to face meeting generally will be better, I like my clients to write a short one page history of the fact and questions they have prior to meeting with them, so nothing is forgotten.