Rescuing Sister From the Dark Lake Meaning & Interpretation

"I was at a lake with my little sister. She ran to the water. She fell in. She could not swim. She went under. I jumped in without thinking. The water was cold and dark. I could not see her. I swam deeper. I saw her hand. I grabbed it. She pulled me down. We both sank. I kicked hard. I pushed up. We broke the surface. I gasped for air. She was coughing. She was crying. I swam to the shore. I pulled her out. She was safe. She was okay. I held her tight. I was shaking. Then I woke up. My heart was pounding. I looked at my hands. They were empty. I ran to her room. She was sleeping peacefully. I sat by her bed until morning."