Need help with Sony Handycam

I have a Sony Handycam (DCR-TRV260) and it has always worked fine. But last night I recorded over half an hour at a party on a tape. I woke up the next morning and filmed something at the end of my previous recordings. When I played it back, only what I taped that morning remained, the whole party was gone. It went from about 0:35:07 to 0:01:33. Does anybody know how to get the rest of the movie back? The camera uses Digital8 tapes and im confused. The only thing i can think of is maybe the camera can record on both sides of the tape? Thanks~