Pentax K-X Problem.. Help! :)

I came home to 4 deer in the backyard.. I was pretty excited and I ran inside to grab my camera.. I get back outside with my Pentax K-X, get it fully focused and the camera would set the flash off but wouldn't actually take the photo.. I changed the dial to a few different settings.. heard some grunting and they were gone. Frustrated I brought the camera back inside, put it back onto manual again and it took the photo.. but it is still selective on which settings it will take a picture from.. anyone have any ideas or suggestions on how to fix this?