Exorcism? I'm no 'exorcist' but I have had experiences with 'possesions', and demon-related problems. I personally, from what you said till now, don't believe she is possesed. I would love to hear more about it.. Any other symptoms? Does this feeling happen when it's light or dark? Or if she's alone? Where is this pressure-like feeling, all over the body or on a certain place? Please tell everything you can come up with. I would love to help, but I first have to see what it is and if I'm able to help.