Had a weird situation yesterday.

Car info:
2004 MCS - Mynes custom tune from back in early 2008 - other performance mods, but they've been on for ages - brake pads/rotors changed about 6-8 months ago with no issues bleeding and no issues with brakes - brake fluid level is good.

I was driving on a city street, 45-50mph in 5th or 6th gear, and the red brake warning light comes on. No brake pedal pressure was being applied. I checked the emergency brake and the handle was all the way down. Light ahead turns red and I apply brake pressure. The pedal gave a great amount of resistance to push, so I applied a good deal of pressure and the car slowed a little, but not enough to stop in time. I then put the car in neutral with the intent of using the emergency brake. Upon going to neutral, the engine red-lined for about a second and a half until I shut it off. During this, I was able to stop in time. I turned the car back on and drove off. About a mile later the brake light went off, but came back on within the next half mile. I finished my drive to work, about 3 more miles, and drove back home later last night (8 miles), without issue.

Any thoughts?