If you have air in them you should be able to "pump up the pedal" and then let it sit for a few minutes. The press the brake pedal down and see if it goes down lower than where you pumped it up to. If that happens you surely have air in them.
Since you only messed with the front I'd think those are the only ones needing to be bled.....and in most cases I'd say only the one wheel where you replaced the line.
Maybe someone who has had the same problem will chip in here.
