Nighttime Recording Of My Ac (Scary)

I decided to go out for the night so i thought it would be a good idea to have my sound recorder going for around 3 minutes. My ac turned on a little after. I caught a few things like fire truck sirens, and some sort of ear ringing sound. Not sure where that came from but it happened. If you have any ideas or theories on what that sound is, don't forget to comment! so enjoy using this sound wherever you like, no credit needed. Thank you!.