My girl and I had sex on January 1 this year. I used protection. She had a period on the 25 of January; it was on time and everything. Her period lasted like 5 or 6 days like normal. Her next period was supposed to start March 1st or something and she says she is late. Now she feels like she's pregnant. We haven't had sex since January 1st and now she thinks she's pregnant because her period. Could I have gotten her pregnant?
Oh, the number of things we need to talk about! Why are you taking the risk of producing a child with a woman you are not committed to with your heart and soul? You know the risk is there because you are worried that your girlfriend might possibly be pregnant despite your use of "protection." Every method devised to control pregnancy has a chance of failure (see "Contraceptives" in Preparation for a Lifetime). I wish I could talk to you face-to-face and find out why you decided to drop your pants. I wonder if your realize all the ramifications that resulted from that decision?
What you and your girlfriend did is called fornication. Fornication means having sex with someone to whom you are not married. Would you take the time to read the article "Why Sex Outside of Marriage is Wrong"? I don't want to rewrite everything there in this reply, but for your soul's sake, you need to understand that God forbade sex between unmarried couples for a reason and that ignoring God's command is placing your soul in jeopardy. "Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters, nor adulterers, nor homosexuals, nor sodomites, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners will inherit the kingdom of God" (I Corinthians 6:9-10).
Meanwhile, the deed was done. Let's talk about the consequences. Your sperm can survive up to six days after you have sex with a woman. If the woman releases an egg in that six day period, it is possible for her to become pregnant. Since she had her period twenty-five days later, she did not become pregnant by you. If she has missed her period since then and feels that she is pregnant, then one of two things is possible. 1) If she is young, very thin, or very athletic, it is possible for a woman to miss a cycle every once in a while. In addition, a woman's menstrual cycle is not fixed in stone, she could go long this month. 2) She is having sex with someone else.
The latter is highly likely. After all she was willing to have sex with you without a marriage covenant, so why wouldn't she be willing to have sex with another man? It would be consistent with the character she has shown. But that means you have another concern, you have exposed yourself to the possibility of picking up a sexually transmitted disease. "Protection" reduces the chance pregnancy and it reduces the chance of picking up a disease during sex, but it is unable to eliminate the risk. For several disease, a condom cannot stop the spread of a disease because many are spread by skin-to-skin contact and a condom doesn't cover all the skin of your genitals.
Secondly, if she is having sex with other guys, what does this tell you would happen if you ever did decide to marry her?
God gives this advice: "My son, pay attention to my wisdom; lend your ear to my understanding, that you may preserve discretion, and your lips may keep knowledge. For the lips of an immoral woman drip honey, and her mouth is smoother than oil; but in the end she is bitter as wormwood, sharp as a two-edged sword. Her feet go down to death, her steps lay hold of hell. Lest you ponder her path of life - her ways are unstable; you do not know them. Therefore hear me now, my children, and do not depart from the words of my mouth. Remove your way far from her, and do not go near the door of her house, lest you give your honor to others, and your years to the cruel one; lest aliens be filled with your wealth, and your labors go to the house of a foreigner; and you mourn at last, when your flesh and your body are consumed, and say: "How I have hated instruction, and my heart despised correction! I have not obeyed the voice of my teachers, nor inclined my ear to those who instructed me! I was on the verge of total ruin, In the midst of the assembly and congregation." Drink water from your own cistern, and running water from your own well. Should your fountains be dispersed abroad, streams of water in the streets? Let them be only your own, and not for strangers with you. Let your fountain be blessed, and rejoice with the wife of your youth. As a loving deer and a graceful doe, let her breasts satisfy you at all times; and always be enraptured with her love. For why should you, my son, be enraptured by an immoral woman, and be embraced in the arms of a seductress? For the ways of man are before the eyes of the LORD, and He ponders all his paths. His own iniquities entrap the wicked man, and he is caught in the cords of his sin. He shall die for lack of instruction, and in the greatness of his folly he shall go astray" (Proverbs 5:1-23) .
In case you missed the analogy, the Bible sometimes parallels sex with thirst. Both are strong desires that are not easily ignored. If you were really thirsty, where would you get a drink? Out of your kitchen faucet or would you take your glass out to the roadside ditch? Any sane person would cringe at the thought of drinking sewer water. Imagine all the germs in it! Solomon then soundly asks why would any man put his penis (his fountain) into a place that was used by who knows how many other men? Imagine how many diseases that woman was exposed to and is carrying around with her! It should be just as disgusting a thought as drinking that glass of sewer water. Keep sex limited to a trust person, the one to whom you are married. Have fun because you know you can trust your partner to be yours alone.