"Rudeness from nurses, after a simple question"

I went to the desk in the ward and asked for a spare chair. Then one of the nurses shouted 'what', in a rude way at me so I asked again. Then another one shouted asking me who I was and which ward I was on. I was very upset. They didn't really try and look for a chair or tell me where I could find one. When I was about to walk away, one of the nurses shouted aggressively that there were two chairs behind the desk after all, as if it was my fault that they weren't seen before.