I am a 21-year-old young lady who has been trying to get pregnant for almost two years. I have been involved with the same guy and nothing has happened. I really love kids and would someday love to have my own. So I was wondering are there any comments on why I haven't conceived yet. I've gone to the doctor to get checked out and she says everything is normal with me and she doesn't see why it should be a problem. And another thing why I think I haven't become a mother yet is because maybe God isn't ready for me to become one. But other than that I am just going to continue to have faith and believe until a miracle happens.
Because you stated that you are "involved with the same guy" for two years, I must conclude that you and he are not married, since marriage is a commitment and not an involvement. That being the case, I am so glad you haven't brought children into such an unstable relationship. Children deserve a mom and dad who are fully committed to each other; committed to the point they have vowed to spend the rest of their lives caring for each other. Only from that stable foundation does a child have the best shot at life.
Please take time to read "Why Sex Outside of Marriage is Wrong." What you are doing is a sin called "fornication." Why would you expect God to answer the prayers of someone defying His will? "Now we know that God does not hear sinners; but if anyone is a worshiper of God and does His will, He hears him" (John 9:31).
You refer to conceiving a child as a miracle, but a miracle is when the natural is superseded. It is not a miracle for sex to lead to pregnancy, it is the natural result of sexual intercourse. See "Do we have miracles from God today?" for more information. But in regards to your question, a woman is not the only one involved in conceiving a baby. If your reproductive systems appear to be in good working order, then the most likely problem is that the "sperm donor" you chose isn't producing viable sperm in sufficient quantities. He should also see a doctor and find out if he is fertile. Many things can cause a man to no longer produce sperm, such as disease or accident, but still be able to engage in sex.