Does a wedding Mass on Saturday afternoon count as a Sunday mass?

If you attend a wedding Mass or a sacramental Mass on Saturday, it DOES NOT fulfill the Sunday Mass obligation.

To fulfill a Sunday or Holy Day obligation, a Mass on the previous day (the Vigil) must start at 4 pm or later and use the appropriate readings for that Sunday or Holy Day. Some Dioceses will allow variations (for example, different readings at a Sunday Confirmation Mass).