How do you know your pregnant after you have sex?

The tummy aches are probably because of the frequent sex, as is the frequent urination. After sex, the body’s natural defense against bladder infections is to make you want to urinate (flushes out any bacteria that may have made it into your urinary tract).

Starting at the last day of your period- you have roughly 2 weeks before an egg is released. The egg stays ‘viable’ for about 12-36 hours. Sperm survives up to about 3 days. If fertilization occurs at any point during these (we’ll say 3) days, the fertilized egg will then float around for a few days until implantation. This occurs anywhere from 3 to 11 days after conception. Once the embryo implants, your body will THEN start to produce the pregnancy hormone. It is usually such a small amount that it goes completely undetected for the first 2 weeks after conception (that’d put you at 4 weeks pregnant)- then, usually by 3 weeks after conception, the body is producing enough human pregnancy hormone that you can detect it with a test. It is also around this time that you can actually start to ‘feel’ pregnant. You may have morning sickness (or afternoon, evening… or be turned off of food ALL day..), tender or itchy breasts, cramping like you’re about to have your period (in abdomen and/or back), and some light spotting is also possible (due to the embryo implanting on your uterine wall).

It sounds to me like you could use a little more education on the matter. What to Expect When You’re Expecting is a good book- but talk to your personal Gynecologist- she can explain the dynamics a bit better.