Took my car to get an oil change. Noticed my car w...

Took my car to get an oil change. Noticed my car was smoking a little, so I check the oil. To my surprise it was very dark and looked like it wasn't charged. I took it to them to check it out. They proceeded to tell me it, that they didn't know what was in my engine etc.. basically telling me it was my fault and they had changed the oil. I'm supposed to drive another 5000 miles on my oil when it's dark as f***. Also received a call about bringing in my other truck for an alignment when it was supposed to be done a while ago....wondering if they even worked on it. Service was ok till now.