Is it possible for a calamity to befall someone as a result of verbally interpreting a bad dream, and what should I do if I have already uttered it?

The interpretation of a dream should not be undertaken by just anyone who lacks knowledge of dream interpretation. Rather, its interpretation is valid only if the interpreter is knowledgeable and correct in their interpretation, as the Prophet (peace be upon him) said to Abu Bakr, "You were right in some parts and wrong in others."

To be safe from a bad dream, a Muslim must adhere to the following prophetic etiquettes: concealing the dream, seeking refuge in Allah from Satan, and resorting to prayer and supplication. This is based on what was authentically reported from the Prophet (peace be upon him): "A good dream is from Allah. So, if any of you sees what he likes, he should not narrate it except to one whom he loves. And if he sees what he dislikes, he should seek refuge in Allah from its evil and from the evil of Satan, and he should spit (gently) three times, and not narrate it to anyone, for it will not harm him."

Additional prophetic guidance was also reported for one who sees what he dislikes, including: changing the side he was lying on, and getting up to pray. Whoever adheres to these etiquettes will not be harmed by a bad dream.