2004 Saturn Vue Breaks

We put a used wheel bearing on the back of my saturn vue (used but in good condition), when we went to put the bearing on we broke the break line so we clamped the hose to stop the leak and got a new break line and installed it and bled the breaks then filled it back up with break fluid, then we put the tire back on, then while we had the car in our garage we decided to fix the abs sensor on the front while the car was in the garage, so we took the calliper off and took the rotor off and put in a used abs sensor in (we took the sensor off another saturn vue we have here for parts), we put it on and put everything back together and went for a test drive after pulling out of the drive way when, I went to break the pedal wouldn't budge and I felt a grinding feeling in the pedal I tapped the break a couple times then the breaks went to normal, we turned onto the highway, and 5 min latter the break light, abs and, tc light came on at the same time and then a few minuets after that the breaks went hard again and we pumped them again and it went back to normal