In my store everyone gets weekends at least occasionally, unless they somehow managed to get weekends off per their availability. In retail, weekends are key, and honestly, TMs who can't work them are kind of a pain. Regardless why you were scheduled, just go in and do your best, like I said before, that's all you can do. In my store, it doesn't mean you are a bad worker. In fact, often it means that you are someone they trust as reliable to actually show up and at least attempt to get the job done.