I recently interviewed for masters programs for Marriage and Family Therapy and on many occasions felt similar to how you are feeling. I interviewed with 4 of the 6 schools I applied to, and while the first one (group) went pretty well, during the second and third interviews (individual) I had issues with panicking and not knowing what to say... so things that probably weren't the best responses came out. My last interview turned out to be okay, and while I did start to panic just a little, it was not as bad as the others and I was able to avoid saying things I didn't really mean/want to say. I ended up being accepted to the last school I interviewed. They definitely know people are nervous in their interviews, so I think they take that into consideration. Did you apply to other schools? Have you heard back from this one yet? I would not give up just yet; you never know what can happen. Good luck!