2001 Mazda 626 just changed brake pads now brakes dont work

just changed brake pads now brakes don't work at all the petal hits the floor with no pressure when the engine is on and builds very little when i pump the brakes but that's when the engine will stall out if i dot apply gas and if i stop pumping the brakes go back to no pressure at at all also my power steering gets choppy and brakes don't engage at all while the car is running when the car is off however the brake will build and hold pressure and it will get hard act like its working but when i try to bleed the brakes very little fluid comes out but the rear brakes work fine
car on or off
the whole reason i changes the brakes is b/c some times while i was driving when i hit the brakes they would stay compressed and the brake petal would get very touchy and i would have to stomp it the petal to get them to release
i cant figure out what is going on please help