The Mastering Engineer's Job Is to Listen to the Big Picture

Go with your gut. Your monitors might be a little harsh in a specific frequency range. The mastering engineer's job is to take your stuff and play the law of averages so that it sounds as good as it possibly can on as many possible systems as it can. So consult trusted ears. Go listen on systems and rooms that you don't own and that you're not at all familiar with, and you get need to get a better sense of the truth here.