Will I fail a check-ride if I do a go-around for a short-field landing?
In general, you get one free go-around.

First of all, any checkride which involves short-field landings probably also involves demonstrating go-arounds.  If you don't do one on your own, your examiner will have to ask to see one later.

Going around when it's obvious you're not going to make your point demonstrates good judgment.  It shows that you're not going to try to force the airplane into an unsafe situation just to hit your mark.  If the runway you're landing on really is a short field, continuing the landing attempt would not only be a bad idea, it would be unsafe, and the examiner would be correct in taking the controls from you, as well as failing you.  If the runway is long and you're simulating a short field landing, the same applies.

If you go around on a short-field landing and then go around on the next one as well, the examiner is going to start to wonder whether you really know what you're doing.  Let's face it, it should not take you three tries to get properly set up for a short field landing, unless perhaps if the day is remarkably turbulent or there is a strong gusty crosswind.  If that's the case, though, why in the world did you decide to take your checkride in those conditions?