Yesterday I flew out on AC972 to Toronto from Grand Cayman. I had a connecting flight to Kingston, Ontario and needed to clear customs before that flight. I asked the woman at the checkin counter to please put a priority sticker on my bag. She said I had enough time for the bag to be transferred to the connecting flight. I told her I would really appreciate it as I had trouble on my incoming flight and my bag was lost for 8 days. During this interaction she tilted her head, leaned over on the kiosk and said, are you raising your voice to me. She was very confrontational and I was quite taken a back. I told her no I was not and that it is not my style. I told her I would appreciate the sticker. She had no compassion or understanding given my previous experience on the incoming flight. I found her behaviour to be rude and inappropriate. I did not feel comfortable raising this at the time as I was afraid she would not allow me to fly. I had a simple request, I have never requested this and only did because of the previous delay. She did end up putting the sticker on my bag, for which I told her I appreciated it very much. This was an upsetting interaction, and I do not feel this woman's attitude was called for.