It’s called clumsiness. You’re just like that. I think certain people are simply more dextrous than others. When your body changes (as in puberty for example) this could be biological, but I think it’s just a general lack of coordination, or carelessness. Maybe you’re absent-minded sometimes? I have off days when I just bump into things and hurt myself, especially if I haven’t slept enough. That’s how I smashed my car.