A childhood belief about ghosts

so I'm Portuguese, and in Portugal there's this legend about a young seamstress, long ago, that was very poor. she made a promised to the Virgin Mary that, if she managed to start earning money with her sewing machine, she would give her first day's pay to the church. but when it happened she didn't, she just spend the money. so after she died (supposedly she died very young and poor) she had to work and work to try and make up for the promise, but she could never because her first day's pay was already spent.

my grandmother was also a seamstress and she told me that, when seamstresses work late, they can sometimes hear the Seamtress' old noisy sewing machine and her crying because she's doomed to sew for eternity.

one night I was staying at my grandma's (I should've been something between 6 and 8 years old) and she was working late sewing some clothes I had accidentally ripped, and I was laying in the couch. when she was done and stopped the pedal, I swear I could hear another sewing machine working! I was scared like Hell!

my grandmother told me the Seamstress doesn't harm anyone, though. she told me she's just a reminder to always keep your promises. I think she was just messing with my head, but I still can't explain where that sewing machine noise was coming from!