You absolutely can't use CP as a determination of early pregnancy. For some women, in early pregnancy the cervix may be low and hard for the first while, while others high and closed, etc, so this is not considered a factor in trying to guess if you're pregnant - it just varies too much between women.
If you think you may be pregnant, pee on a stick!
A good place to look is fertiltyfriend.com, they have loads of good info. Also, Mrs Canada is correct. There is not a set pattern in the early stage of pg for cp. Good luck :)