Yes, you are being set up to say something "bad" about yourself. Every teacher (and student teacher) has had a discipline problem in class. You need to select a problem that helps you focus on two things: (1) a problem that does not reflect badly upon you as a teacher and (2) a problem that you quickly solved positively and creatively.

One example might be this: "I had a student once who asked if he could be excused from taking a test. I told him he had to take the test just like everyone else in class. He refused and put his head down on his desk. So here is what I did...." At this point you can interject some of your own philosphy of teaching. You can point out how you talked to the student in the hall to find out what was going on in his life that led him to refuse to take the test (was his dog hit by a car last night?). You can continue with what you said to convince him to take the test (did you ask him to take the test anyway and you promised to let him take a make-up test if he got a poor grade?). And conclude with a positive ending... "He ended up doing quite well on the test anyway."