Of course not, being straight doesn't make you bad, just as having any other sexual preference does either. You are who you are, who've you've always been.
It's not something you get influenced by. If one would think like that, then you could wonder why there is anything but straight people in the first place, because surely your parents must have the biggest influence on you.
There is no use in trying to search for a logical explanation for something that doesn't have an answer. It just is. Some people take longer to discover who they are, some deny it, suppresses their emotions and needs out of fear of being rejected and judged. It's not a choice you make, not a decision someone can push you into. You, and only you, can answer the question for yourself. And you should never, ever, be ashamed of feeling the way you do, or worse, for what you don't.