To dream that you are under a spell indicates that someone has a powerful influence on you. You may be taken for a ride or being manipulated in some waking situation. Alternatively, the dream is a commentary on your waking relationship and how deeply intertwined you are within a relationship.
To dream that you are casting a spell implies that you are undergoing an inner transformation. It also means that you are manipulating a situation. Or perhaps the dream is telling you that you are being too controlling.
To dream that a spell is being broken means that you are thinking for yourself and not allowing others influence your decisions.
Dreaming of a protection spell written in red is a message from your subconscious that you need to be more cautious.