You may be pushing the shutter button too quickly. When taking a photograph, push the shutter button down halfway and allow a brief moment for the camera to focus before continuing to push the shutter button all the way down.
The battery may be inserted incorrectly. The battery does not need to be forced into place. The blue tab should slide into a groove that holds the battery in place on the negative-positive side of the battery. You must also push the battery all the way down, so that the spring is compressed, and the blue tab locks the battery into place.