I've heard them for quite a while now, maybe the past two months or so. Whenever I used to, I would put it up to myself listening to music very loudly in headphones. (It helps calm down my emotional attacks) but just now it sounded as if I was hearing people have a conversation, only dulled. Like I was underwater. 

It really frightened me. 

Is this a trigger for something more then bpd? or is it normal?