You were taken into the Black Pearl. When Captain Barbossa figured out you weren’t a Turner he backhanded you, causing you to fall down by the water as his crew starts to turn on him. Will had gone with Jack to save you, and as he looks around the cave he sees you by the water. He silently swims up to you and gently covers your mouth to keep you quiet

“Come on, I’m getting you out of here.”

He says and silently helps you out of the cave