Can you know your pregnant even if you had your period?

Take a pregnancy test.

it is possible yes, maybe a bit early to be pregnant, but just trust your body

Yes you could be. In some rare cases women actually continue to have regular cycles during a majority of their pregnancy. Most home tests do not detect pregnancy until you are about 20 days after your last cycle, or 5-6 days prior to your missed period. A more accurate test is an hCG (Human chorionic gonadotropin) or serum pregnancy test. This tests the peptid hormone produced by the embryo after conception. In rare instances you can have a positive hCG, such as if you have certain types of cancers such as choriocarcinoma, germ cell tumors and trophoblastic tumors. Typically however, ovulation occurs about 14-16 days before women have their period. The egg stays alive for about 24 hours once released from the ovary. Sperm can stay alive inside a woman's body for 3-4 days, but possibly as long as 6-7 days. If a couple has intercourse before or after ovulation occurs, they can get pregnant, since the live sperm are already inside the woman's body when ovulation occurs. Thus a woman can become pregnant from intercourse for about 7-10 days in the middle of her cycle. So there you go. Susu

If your period was regular for the months before your unprotected activity (the day before your period started) it is not likely you are pregnant. There may be some other cause of your physical discomfort and you should see a doctor for a diagnosis.

Nausea and vomiting (if you are prone to morning sickness) don't normally start until the sixth or seventh week after you conceive. Take a home pregnancy test. Contrary to what you may have been told, the home tests are sometimes capable of detecting pregnancy one to two weeks after conception.