Let me explain the situation. Today is Oct 31, 2012. After I got my October pay-slip yesterday I had the following conversation:
Me: Hey guy, I have a question to ask you about the pay-slip of the last month. I think the number is incorrect.
X: It is $10, is it correct?
Me: No, I mean last month (I mean September) not this month.
X: Last month? Okay.
I want to know, did I use "last month" correctly in this case? I used "last month" because this month is not passed yet, so I used it to refer to the month before this month. And if it is incorrect, what word should I use.