What does it mean when you hear bells ringing?

Twice today I have heard what sounds like Tiny Bells ringing, not in my ear but externally. No one was making these sounds, I heard it 8-10 minutes before I took a nap and 10 minutes after I woke up. What are the possible reasons for this? I would like to hear reasons that involve both the spirit world and our world.
Everyone wants to be a comedian I see, look it's not anything nearby, this is something I hear externally. It's not a medical or mental condition! If you don't have any intelligent answers, don't say anything!