Yeah, that doesn't make much sense. I am sure that most, normal, people that walk in and see you are busy on the phone are capable of understanding that you will greet them and assist them as soon as you finish the phone call.

I feel every day that my job is beneath me. I hate having to defend myself to my clueless, idiot boss. Trying to explain anything to her is as productive as talking to a brick wall and triggers my (supposedly not caused by work) anxiety.