I have had experiences as well, I often feel what I could only describe as gravitational anomalies, like a sudden shift in gravity, direction, intensity, etc... this is similar to what you would feel standing on the upper level of a parking ramp, large building or shopping mall as people are moving about.

Other people I've asked "did you feel that?" don't have a clue so either I am whackado or I'm feeling something real.. no idea really...