I dnt think u have n e thing 2 worry about with u having a normal period still...
http://wiki.answers.com/Q/Can_you_be_pregnant_but_still_have_your_period
here is question & answer about this
you should wait at least 2 weeks after the last sexual encounter to take an hpt. but like kimberlee said you don't get a period while pregnant. you can have bleeding but that is only if you have a medical condition. (there's a few but i'm not sure what they are. you would have to ask your doctor what they are and if it is possible for you to have one of them.)
WAT IF I HAD UNPROTECTED SEX ABOUT 3 WEEKS AGO AND LIKE TWO DAYS AGO I HAD SEX AGAIN.....WILL I STILL BE ABLE TO TAKE A PREGNACY TEST....WILL ANYTHING SHOW UP?????
You don't get your period while pregnant, you can have pregnancy related bleeding, but not a period. As long as your period is starting within a week of normal time to start, and it's lasting 3-7 days I wouldn't worry about pregnancy, cramps also come along with pregnancy. If you think you could be pregnant take a test two weeks after your last unprotected sex encounter and it should show positive if you are. Good luck!