The other thing is, really wash your hands before checking the cervix. The vagina is one of the cleanest spots in the body, with specific flora that keep it healthy, and hands are able to be one of the most bacteria-laden parts of the body besides the anus, pretty much. Don't introduce foreign bacteria, viruses, fingernail dirt, sweat, funguses, yeasts, anything if you can help it. Better not to check the cervix at all than to give yourself an infection. Good luck!
I can't tell you about if your cervix is open our closed but I know that also say to check how low or high your cervix is and if it's soft or hard. You just have to do it awhile and you learn what is low vs high (ie knuckle deep to reach it vs full middle finger vs full ring finger). Then soft vs hard would be the difference between your lips and nose. I know way to much information, but you asked;-) It is also best when you cervix is wet (ie egg white stretchy discharge). Just remember most fertile is SHOW--Soft, High, Open, Wet. Again sorry I can't help with open vs closed. Good luck.