Some one wired that thing wrong.. obviously.

There should be 2 switches on the brake pedal. One for the lights and one for the emergency pump on the brake manifold.

Sounds like someone pulled the brake lights from the wrong switch and it was actually the brake booster switch..

No turn signals is probably related to brake switch issue. Just start at the flasher and move either towards the fuse box or towards the signal switch..

Good luck out there..