Good infos from lepus.
Chances are to be 'inner' blocks and parts of your psyche,rather than external spirits.
In that case,no amount of room cleansing will work.In fact placing them outside of you,will give them more power to manifest externaly.
If the problem is coming from you,a herb bath will have good results,and you'll feel the difference immediately.
I don't know much about herbs,but i vote for laurel (bay leaves).
Put some dry bay leaves into water,leave them for some hours,and then use the water over your body.
Feet,head,forehead,hands or even better your whole body.
Also i've heard about camphor.It's unpleasant to parasites and low level beings.You can buy some discs from the super market and burn them over charcoal.