The brakes That weren't there

"I was driving home and the brakes just weren't there. Not gone exactly. The pedal went down but nothing happened. I remember pressing harder, like that would do something. The exit was coming up and I needed it, but the car kept drifting toward the guardrail, slow, like it was deciding on its own. I turned the wheel and it turned but not the amount I asked for. Everything was delayed. I tried to downshift. I don't even know how to downshift. But in the dream I did and it didn't help. There was a truck ahead and I was gaining on it and I kept thinking, okay, this is it, and then I was just... past it. No crash. The road was empty. I pulled into a gas station and sat there with my hands on the wheel. The car was off. I don't remember turning it off. An attendant knocked on the window and I rolled it down and said "I'm fine" before he asked anything. Woke up with my foot pressed into the mattress like a brake pedal. Released it. Lay there. Drove to work extra carefully. Nothing happened. Of course nothing happened."