Background: When I am not at university I work the summers and have been working for this (very) small food service business for the past 3-4 summers. I am (other than my boss who is the owner) essentially the only other person who works there. We have had a very good relationship and in my opinion I have been an extremely good employee for these past years.
Yesterday, however, he left the kitchen for around 1.5 hours for an unknown reason and gave me a list of things to do. I did everything he asked including going above and beyond to clean and organize our entire kitchen. However, when he comes back from this mysterious appointment instead of seeing everything I went above and beyond on the first thing he sees is one tiny error (some plastic containers I forgot to move to a different area 50 ft away) and absolutely flames me for it. I stay as professional as possible during this, simply nodding and showing understanding towards his anger, and assume we will move on (as more work still had to be done). Later that night however he continued to act very cold towards me. When I talked he would not respond and after giving my opinion on something he asked why I “had a fucking opinion about everything.” At this point I just shut my mouth for the rest of the night not wanting to make things even worse and only giving him short concise answers but this just made him angrier and verbal abuse in the form of many swear words thrown my way became constant for the rest of the night. At this point I was about 9.5 hours into what turned out to be an 11.5 hour shift and was completely dejected. Just thinking about it is ruining my only day off today. I have enjoyed working for him before but am not sure what my next step should be.
Edit: At one point he told me that he’s paying me x (an average wage here that he believes is very high I guess) and should expect absolutely no mistakes.
Edit 2: He says that I should know how he wants everything done (due to my prior experience) but he has either ADD or some other organization problem because he changes how he wants things done/organized every few days/week. (This is not even just my own hunch everyone who has ever worked for him thinks he has some problem related to this including his own wife).
Edit 3: I must have had some resting bitch face after stopping talking because he basically added “unless you quit” to everything he was saying was coming up in the future, despite me not doing or saying anything that indicates my quitting.