1996 Mazda Protege sudden electrical problems

I recently bought a 96 Mazda Protege and in the first week the dome lights, trunk lights, windshield fluid pump, and factory keyless entry have all stopped working. I've checked the fuses under the hood and the fuses under the drivers side dash and everything seems to be fine there. This car also came with a stereo that didn't have a face plate so I've tried to hook up a new stereo, but that doesn't seem to be working either. Are all of these things on the same circuit somehow? Is there a big relay somewhere that I need to check? Thanks in advance for any help.