I don't think that you did anything wrong except to listen to the guy that said not to disconnect the head before pulling it off. I always have problems getting high pressure into the tire with these short pumps and it seems to take a couple of hundred pumps to fill the tire. I got a topeak turbo morph and its rated at 160 psi. I don't know who can pump it to 160 psi, I can only get about 90 psi until it starts to hurt my hands. I will pump it up with this pump then top it off with a CO2 inflater.