I applied to the PSU HDFS, but I am not the lucky guy (or girl) who was accepted.... Still waiting. What programs did you apply? (I only did PSU for HDFS - Methodology, others are in quant psych)
I agree that it shouldn't matter that much and it's highly possible that already saw it but still chose to interview you. I made two silly typos as well..... and beat myself up for a couple days..... Try to convince yourself "It's better to get rid of that guilty feeling and focus on preparing..."