Dream about someone banging their head is sadly your anxieties about trying to fit in or being well-suited for your changing role. Your are not holding yourself accountable for how you are acting or feeling. Some aspect of your life is spinning out of control, especially if you are having difficulties in communicating others. It expresses your subconscious desire to leave that something behind. You are not letting the negativity get to you.
Someone banging their head dream refers to a situation where you have almost everything that you can possible want or need. You need to express your sadness and not keep it inside. You feel that you cannot fend for yourself and feel you do not belong. It is a premonition for aspects of yourself that are being joined together as a whole. You need to learn to express your negative emotions instead of keeping it bottled up.
If you dreamt about someone banging their head:
You are a force to be reckoned with and virtually unstoppable. The position of the heavenly bodies today creates a situation in which you have supreme right of way. A certain person, for reasons known only to you, is now subtly under your control. How you deal with this will not only increase or decrease the respect they naturally feel for you, but will also affect the partnership itself.