Dreams about feeling lonely in social situations can reflect your current feelings or fears about connection and belonging. In your dream, being on a class trip suggests a time of learning and social interaction, which may contrast with your experience of isolation, especially since you noticed everyone else with someone.

Your dad's presence could symbolize support or guidance, but the feeling of loneliness indicates a desire for deeper connections or companionship. This dream may be prompting you to explore your relationships and consider how you can reach out to others or express your feelings to those close to you.

Consider reflecting on your current social interactions or any feelings of isolation you may be experiencing in waking life. This dream could be a nudge to seek connections that bring you joy and fulfillment.