I'm fairly certain that anyone who has ever used a telephone has at least once in their lives dialed a wrong number (or texted a wrong number in the modern era). It is not a hard thing to accidentally hit a number out of sequence, or a wrong digit entirely. Usually, most people aren't too bothered by it, but that doesn't apply to everyone. Sometimes you may even have a pleasant conversation or make a new friend from a misdialed call.

Accidentally texting the wrong number is pretty much as awkward and embarrassing as it can get, but it all depends on who the person on the other end of the line is.