gear shifter movement

Get to a gas station pump put car into park. My car starts rolling forward and I let it roll all the way into the parking space. Shut off my car go in side come out. Won't start no sounds battery is good. After some investigating I figure out that my shifter (I have the kind by the cup holders not on steering wheel) won't go all the way down to the drive selection. Almost like it of centered. So it's not going all the way into park (there for not starting up) I tried to find the neutral and starting up in that selection but couldn't find it or something. Does this sound like the gear shifter box or something in the tranny what's your thoughts. Thank you very much