if you are checking for the first time it can be tricky....but I will try and explain it the best I can...albeit forgive me if this is graphic....
if you can feel your cervix, here are two scenarios:
#1: reaching up you can immediately feel your cervix-which has the feeling of the tip of your nose...a little squishy maybe. You will also feel a small opening...almost like a very small hole. It of course will be moist but will somewhat feel like you are poking your nose/nostril. If this opening/hole is opened enough that your fingertip can fit into it (dont push), than your cervical entrance is considered open. Upon reaching up to find yoru cervix, if you donthave to reach far, meaning you find it almost immediately AND you are met with this scenario, than it is likely you are not pregnant....unless it is just very very early in the cycle...than all of this would be normal.
#2: reaching up, you do not immediately find what I describe in #1....rather you have to do some....reaching because it is high up there and when you do find it, it really does feel like the very tip of your nose...very firm and solid. You might still feel the opening/hole of your cervix but your finger will barely, if at all, fit into the opening (again, dont push) and it will be very tight/firm on that opening. If you are met with this scenario, especially if it is the last week in your cycle, than there is a very good chance you are pregnant.
THIS IS NOT 100% RELIABLE! So please dont count on this to be totally accurate. Do a google search for "cervical changes in early pregnancy" and you can find more about this. Each time I have been pregnant, I have known from cervical positioning first. But everyone is different.