Well i can design a test for this .... Would you be willing to be the subject and film the test with someone electrocuting you ?? (or a range of other "things"...Better be sure something will work before you consider this action over something else in actual life death scenario)
As for the original poster's dilemma .. You can use some testing of your own to solve your problem
1) Try to sniff out where the scent is most strongest and it may lead to source.
2) Find out what changes around your immediate environment weekly. Like some event happening outside your room or within that might cause the scents.
3) Talk to others and find out if they can smell the same scent in other places and in your room as well.
4) Try shutting one point of access to your room (for the scent like a windows etc) and opening others. Repeat this for all access points and if for some point the smell dies down and is not replenished this means you find your source. If it still persists after doing this for all points that it can mean that there might be something from within the room or some access point within the room you might not have considered (vent etc).
Try coming with more of your own ideas for narrowing down the culprit. It might go away on its own (Well nothing justs vanishes. It might be that the source has been removed one way or another). If there were supernatural presence in your room causing the smell we would be having weird unexplainable smells all over the globe and it would have been a SERIOUS problem however to the latest of my knowledge this is not the case
(besides arent supernatural presence associated with bad smells like rotten eggs etc)