This dream may reflect feelings of conflict and tension in your waking life. The school represents a place of learning and growth, but in this dream, it becomes a source of conflict and argument. This could symbolize a situation or relationship in your life that is causing you stress and frustration. The presence of your friends may suggest that these issues involve people close to you. The argument could represent a disagreement or clash of opinions. Walking out of school may symbolize your desire to avoid or escape the conflict. The girl in the hospital gown could represent your own feelings of vulnerability and instability in the face of this conflict. The ambulance and mention of a mental hospital may suggest a fear of losing control or being labeled as unstable. Hiding behind a tree and hopping from roof to roof may symbolize your attempts to avoid confrontation and find a safe place. This dream may be a reflection of your fear and avoidance of conflict in your waking life, and a reminder to address and resolve these issues in a healthy way.