Mermaids war from themselves

there was a Queen mermaid living in her water castle she had a daughter her name was Nina. The city of mermaids was rich. They were happy with their city. One day Mermaid Nina gone on the upper level of the sea secretly to see the world when she gone outside she was harmed by an arrow having a gelly type thing on it. It was hurting badly she started crying and then she thought to return to her castle cause she saw a ship coming she was swimming so fast and gone in her castle then she gone in her room and started crying then suddenly she fainted...