I was never diagnosed with anxiety disorders nor do I believe I have one, but I want to hear advices from people who go through this commonly.

I often get anxious in school, such as when going into a classroom and fearing that I went into the wrong classroom, or that I am too late or too early when all of my classmates have already went to the other classroom. Sometimes I think of an answer to a question from the teacher, then I doubt my question, even while having the entire process of solving that question in a sheet of paper. I often can't deal with these sudden anxieties, as I often don't have enough time or resources to prove to myself that I am right. How do you deal with these situations? I tried the common deep breaths or reality check methods, but it doesn't seem to help.

Thanks in advance.