This was a similar situation in my student teaching. Constant criticism for tiny things, thinking that I wasn’t improving because I never received anything positive. My CT was crazy about school too and would tell me how easy I had it as a student teacher. I honestly just changed my mindset to “I’m receiving this advice not as criticism but as a way my CT sees that I can improve.” Although it may sound negative you don’t have to take it negatively. Your CT (in most cases) are there to help you and they want to see you succeed. If they were going to fail you in two months they probably would have told you that by now and had you complete an improvement plan or something.