pardon the wrong grammar :P

i was taking pictures of my friends when i used my camera (Fuji A850). After taking shots, typically, we would browse the pictures. As we were doing that, the lens cover suddenly closed. Normally, it would that so as to save eneergy, i think. So at first, i did not find it suspicious. When we decided to take pictures again, i turned on the cam. it turned on just fine, except for the lens cover.

i don't know why it did not open. what should i do? some said i should blower the lens so as to get rid of the debris stuck on the lens cover.. should i do that?.. does repairing a camera cost as much as buying a new one?

help please..