Ive had new plugs that went in snug on cars before, to where I could not screw it in with the extension on the socket, I had to put the wrench on it.
I know what you mean, its a sick feeling. As long as it went in with pretty much the same slight torque all the way, like two fingers on the ratchet wrench you are ok. If it was cross threaded I think it would get harder and harder to screw in as it went.
If you did cross thread it, its not the end of the world, you can put a helicoil in if you need to. When you take it out next time check the threads on the plug for stripped out aluminum.