Since a lot of professors teach as adjuncts, they are only employed by the uni during the length of your class. This can make them hard to reach once the course is over. Likewise, a lot of full professors go off and do research over the summers, so they can also be hard to access once class is over.
But how did you try to reach her? If you sent her an email, that's not good enough. Send her another email now, and also leave her a voice mail message, and also talk to her department secretary to find out if she's still around. Ask the department secretary to help you, please (be very nice when you ask this) because you're desperate, and can she please leave a not in the professor's box for you.
As it stands right now, you're about to be academically dismissed from your school, and you will lose your ability to get financial aid. You need to talk to your advisor as quickly as you can. Your advisor can tell you exactly how to appeal your grade and so on. She can also tell you how you may be able to appeal your dismissal. Worth the conversation.