Hello there. I borrowed one of those old fashioned Pentax camera from my uncle to take some long exposure photographs of the stars for an astronomy project. While exploring the functions of the camera, I managed to get it jammed. The advance lever will not advance and I can not see through the viewfinder. My guess is that the camera thinks I need to take a picture before advancing again. In Auto, M, 125x, and B modes... I can depress the shutter button, but nothing happens. In L mode, the shutter button is stuck and can not be pressed in when I press it. I'm not sure what I can do from here, so I'm asking to see if any experienced photographers could offer me their insights. Is this just a simple problem that I can fix, or should I be looking for a place that repairs cameras? If I have to take it to get repaired, is there any advice I should be given? Thanks in advance for all replies!