Choke zx6r 2007-08 problem

Hi guys, I have problem with my zx6r 2008. I was working on it and I got off the airbox and replaced my spark pulgs. I assembled everything after that and when I turn on bike it was working on 1500 RPM. That wouldnt be a problem but it suppose to work on 2800-3000 because it was cold engine. I tried a few times more to turn it again but it was same situation again. Before my service it was working normally. The bike works great but I noticed that problem with RPM. Does anyone know what is a problem and is it a big thing?