I feel like if you put in a lot of effort into anything, it is almost always a win- win situation. I remember when I sucked at drawing or running, but I tried my hardest and I made some massive improvements and became really good at it.
Even if you fail, it is always good experience in my opinion.
You're trying too hard when you try to fit in a certain clothing style but fail at it pretty hard, when people with a lot of experience know that you're going to fail regardless (think school or work) or when you're trying to get something that you won't get whatsoever (like a GF/BF). Usually trying too hard involves nuisances for people whatever you're trying to do.