Emulsion Issues

Hello, I have been printing shirts for a while but I recently had a problem with burning my images into my screens and washing out the emulsion to recover the image. As I burn the image into the emulsion I notice don’t see the image in the emulsion after I remove the opaque design. I then go to wash it out and it’s difficult to get the design out but it eventually starts to come out however the rest of the emulsion starts to come out too. I haven’t started doing anything different to change how my setup works. I burn the emulsion for around 12-15 minutes and I use a general household light bulb (which I have been using for months). I’m not quite sure what it could be. Attached is pictures of my screens after they are messed up. Thanks in advanced for any responses.