I have had some strange things going on,smoke alarms going off which are not connected to mains or battery,windows opened when Ive checked they are shut,items moved around the house,feeloings of someone behind me ehilst laying in bed,floorboards creaking and nobody there and pictures falling off the wall.
Are these signs from someone who has died or am I being silly?

And you still live there? No seriously, go talk to a priest. Do you live alone or do you have a young family. Make sure no one is simply playing a joke on you.

I have been to see a psychic and she has told me it is my Brother in Law who is doing this,I didn't tell her WHAT was happening but she told me exact things and said he thought I would find it funny! He died a few weeks ago.

Have you tried asking what the spirit wants? It may simply be your brother in law trying to let you know he has reached the other side and wants to say hey. Do you get a bad feeling from the events?