I constantly hear a mysterious chirping sound
It started within the last few months. Like I'd be in bed and hear a chirping sound, like a high pitched "wee-woo!" I thought it was the upstairs neighbors ringtone because they always have their sh** up super loud. But now I've started hearing it in a friend's building too, at least 3 times already. Seriously wondering if it's an auditory hallucination or spirits trying to get my attention. Is this normal?