Human mind is an enigmatic organ in its steady-state. Subject it to stress and unfavorable environment, one can really go totally loco. By suggesting someone to do PUJA SUJA ( ARE YOU FRIGGING KIDDING ME???), you are perhaps avoiding a major problem in your life. Exercise, diet and stress probably has to do a lot of it. 

I have always been baffled at the fact that majority of such incidents happen with people who are psychologically and physiologically weak. Not to belittle your problem my friend, if you think your daily life activity has nothing to do with it, kindly refer a counselor in your univ or your area. I had a cousin who claimed to have a similar syndrome. As soon as she left Nepal, her syndrome vanished into thin air. The joke was that the" bhoot" didn't get the visa.  but it was obvious that she was under tremendous pressure from family, friends, and relatives in Nepal .

Sgy,
There could be so many plausible reasons of your experience, yet you resort to paranormal as being the most plausible. Kudos!   After all, we're brainwashed as kids of all this nonsense that it becomes ingrained in us. One free useful advice: Do not talk about it in your workplace (For obvious reasons).