Hi guys, I recently got a Pentax 6x7 from ebay. I've been putting my first roll through it and for some reason the winder is continuing past the 10 shots I should get on my 120 film roll. Currently the counter is at about shot 13 - I'm hesitant about opening it up. Any tips? The switch on the side is set to 120 and I'm fairly certain I set the backplate to 120 also. Let me know!