computer taken over?

i was playing yesterday and somehow my pc woke up from death or sumthing, and started moving my mouse.
i found it pretty interesting so i didnt do anything, until i noticed it opened my bank grabbed my cash and clicked the [x] button >.<

soo thats the second time for me, last time the same happend but i had the cash in my bag, so it only clicked the [x] button.

if anyone can lend me some money to build op my cashpile again?
or tell me how i prevend my computer waking up from death again.
tnx.