The tambourine and the basement

I remember being in approximately 2nd grade at church. I had to go to the bathroom and those were located in the basement. I excused myself and went down there alone. I was in the stall and heard a tambourine noise in the distance. Thought nothing of it until it started getting closer and faster. I started to get freaked out because I'm alone down here and there is no tambourines in church it was just the organ. At one point it was right outside my stall and then it stopped. I came out of the stall and booked it up stairs like my butt was on fire. I told my brother who thought I was insane. I've been down there before and nothing happened but it was always dark and creepy and I always felt watched like I was never truly alone. It wasn't so bad if my brother went down there with me but when I was alone I felt scared.