Ever since I got my car two years ago, the breaks have been tempremental. They work 90% of the time but if I have to stop in an emergency, it feels like the break is actually touching the ground outside. Three weeks ago I got new break pads but yesterday I had to stop at a junction and after applying the breaks in plenty of time they wouldnt work and I was about half a foot over the junction line. Since then they are working ok but still dont feel 100% , any idea what it could be. My car is a V reg Megane.