What should I do if professor grades unfairly? Background: 

I take the required course through another university in order to graduate earlier, and that is how my nightmare starts. 

From the first few weeks, everything was going fine; however, after the mid-term, the professor approached me and said she needed to talk to me. 
When I went to see her, the first thing she asked me to do was read aloud of the instruction of the exam (which I felt being insulating because English is not my native language). The instruction is basically said this exam contains the answer key, do not take them with you or take any pics and hand in back as same as it is. 

After I read it, she asked me "where is the answer key"? I immediately realized that she thought I took her answer key. I told her that I did not take your answer key, because when I reviewed the exam, I thought the scantron was the answer key. She said it's fine and she would take me out of the report (What report!!??) Per my understanding now, everyone should have an answer key, instruction guild, and scantron on the exam when she hands back for us to review. However, what the hell would I know it as we just had a few mins to review our exam back at that time?  

BTW, I remembered when she handed in the exam, I saw my classmates do not even have instruction paper being stapped on the exam, meaning that it may be a simple mistake that she forgot to staple the answer key on my exam. 

After this incident happened, she kept giving me lower grades. I compared my papers with my classmates. Most of them got full points without following her instructions or writing properly. She makes comments saying I did not answer questions, but I did answer all the questions in my paper. My friends reviewed my papers and all agree with me, so the professor may not even finish my paper. 

I am so upset and I really need to pass this class. What should I do? Go to talk with deen or persons with higher positions? I just felt like because I am not coming from the school she works, so she treats me differently. However, ironically this course is ethics. She was not supposed to accuse me of things I have never done and based on her bias to treat me differently compared with others. I really don't know what to do...
Two steps:


Ask her for a meeting in her office where you can talk in peace and
phrase your concerns in a friendly but clear way. First say that
your feeling is that there is a problem but you are not exactly sure
what it is and why it is there. Then ask what you can do to improve
the situation. Don't make any accusations ("You grade my papers
worse!!") and dont get personal  ("You don't like me!") that will just make her defensive. Rather say
things like "I feel that something in our communication is not quite
optimal and I am here today to ask what I could do to improve the
situation.".
If this meeting does not improve the situtation then you will need
to go higher up in the food chain and talk to whoever this is.