after school

You are a boy, about 12 years old.
After school, you were walking home. It was winter. It was cold outside, your breath was steaming. Snowflakes were falling. You were walking with a friend; your friend was catching snowflakes with his mouth, but you lived beyond your friend. You saw your friend (Vlad) off and continued on home. It was evening, at home, frosty, snowing. Suddenly, you saw a dark silhouette on the playground; it was that of a teenager. The silhouette was sitting on a swing, his face buried in his knees. You didn't approach; you could hear the swing creaking and the trees rustling in the wind. The teenager was still sitting on the swing, motionless. He looked about a teenager, and he had a black jacket and red hair. You walked slowly; your cat, Barsik, was waiting for you at home. Your parents were on a business trip, so you stayed with your sister. Your sister is a difficult teenager, so she often stays out late, and she wasn't home. You still had a long walk home. It was 2017 outside. A man was walking towards you. You didn't notice him in a hoodie. The teenager was also sitting on the swing, and you thought he'd just had a fight with his parents. The man walked faster than you and left, but suddenly you felt something cold on your neck.