<human>: Can you summarize the given text in a few sentences?

I'm taking a once a week, 3.5 hour, physiology course over the summer. I have taken this professor previously and kind of knew what to expect, as far overly sensitive. To give you an idea, he spent 30 minutes of class last quarter lecturing us about "talking behind other people's backs" because someone gave him a bad online review. 

This past Tuesday we had both a midterm and a lecture. After the midterm, he asked everyone how it was. I gave some feedback, and he said we could talk about it during the break. I replied that it was fine to talk about during office hours. Fast forward 1.5 hours, he ends class and asks if I want to talk about it. At this point, I haven't eaten in 8 hours so I said it was okay, assuming again, that we would just talk about it in office hours.

He went off about me to two other students after I left, ranting and complaining about me for awhile. One student, who is my friend, was in the back not even listening and he pulled her into the conversation. Apparently, he thought I was ungrateful because he ended class early for me specifically, which I obviously did not know since we had also reached the end of the powerpoint. 

I find this really inappropriate, but I'm also now afraid it'll affect my grading. I'm not sure what's the best course of action. I was debating on bringing it up in office hours, but I know he's a little unstable and I also don't want to implicate my friends. I was also thinking of going to the department chair but that seems intense. 

In addition to this, he sends contradictory emails about when things are due (i.e. this online quiz is due at 9pm; just kidding, I'm going to take it down at 12pm). His exams are full of mistakes, and he doesn't let you take them home, giving you only ten minutes in office hours to review them. These are some other things that bother me that I feel like are never addressed when I, or my other classmates, have brought them up in office hours.
<bot>: My professor complained/ranted about me to other students, which I find a little inappropriate. He has some control issues and doesn't seem very emotionally unstable. I'm afraid it will affect my grade.