I wonder if perhaps what you are experiencing is some kind of panic attack symptom? Are you at all claustrophobic? In my past experience of panic attacks, before one is about to happen, I might get this overwhelming feeling...a bunch of verbal thoughts in my head piling up at once. A swell of thoughts that come across sort of as murmuring, mostly incoherent. And an odd surreal sensation. Also, panic attacks and crying usually go hand in hand for me..
:oops: Of course, if you feel this is something different, then you must go with your instincts.