i have some weird problem

i have BT5-Gnome-64 installed on a little netbook working perfect.
except when i go to sleep at night and leave the netbook on and yes this is realy true no jokes.

when i wake up i go and look at the netbook and it tryed to change my background about 25 times and opened firefox 2 times.
and it moved gerix-wifi-cracker that was open to the second screen instead of the first and it closed my airmon-ng that was open to sniff for WEP packets.

now is my question how is this possible??? and how can i solve it?

i have noticed it 2 times now at night but not over the day and i have a camera in my room no one touched the netbook at that night not me and no one else.

the netbook has the standard BT5-Gnome-64 version installed
and has the following specs.

Intel N470
2 GB Memory
64GB SSD
no battery installed
only working on adapter

hope anyone can help me thanks in advanced