I think you are saying that the "water that came our was only a trickle, but it squirted out". This could be OK, and then it could be the problem. Place a flat bowl or something to catch the water so you are not concerned about ruining the floor or carpet. Now reopen the petcock. The water should come out under pressure - 15 to 20 PSI, and it should come out continuously. If the furnace is running, it will turn to hot. If you are getting hot water but the radiator is not warming up then the water is not flowing through the radiator. Go into the next room, or the next radiator and bleed it. You should actually start at the first radiator, bleed it, then move to the next, etc. Eventually you will get rid of all the air. Remember to keep supplying more water - keep the pressure up. If your "trickle-squirt" keeps up you could have a blocked line, but my bet is you do not have enough water in the system, under pressure. Keep the pressure up and the trickle squirt will turn into a steady stream. Then move downstream to the next radiator.