I think you’re both right, but this is a great reason for ISO8601. This weekend is the weekend in the current week. In most of the world it’s Monday-Sunday which makes this way clearer, in which case he would have said “next weekend” and you would be completely correct, but if you’re in a country that starts on a Sunday then “this weekend” is two things. Sunday and Saturday, with 5 days in between. Since you were already in part of the two parter you could only be referring to the next part, the upcoming Saturday, part of this week.