I don't know if this is too late if you got a new preceptor or not but I had the exact same thing happen to me. She treated me the same way as you explained. Our personalities just clashed that's all. I need someone to be patient and show me, not tell me what to do and expect it to be done right. three weeks into my 1st job she told me that i should be up to four people and i couldn't even do 3 comfortable (because she threw too much at me and expected me to know where everything was and how to do everything). So I got a new preceptor. He is amazing and my confidence is back up. you have to get with someone who fits you! hope you are doing okay now!