Current intern here!
The interview process is so stressful and draining. I wouldn’t be concerned about the length of your responses. If you’re giving great and relevant info, share it with them. I know I felt as if I was taking too long to answer or that I was repeating myself. Something I did to help (and if you’re feeling anxious about your responses, this may help) was to literally take a moment to answer the question so I could gather my thoughts and take a quick breath. It’s also okay to ask for a moment if you need to think about questions surrounding conceptualizing cases or going through vignettes.
Overall, though, just know the interviewers also know you are probably super anxious in the interview. They all understand that 😊 don’t be too hard on yourself! It’s a stressful time and definitely understandably so. So just be you in the interview.