Hi I had sex with my boyfriend this past weekend and now I am experiencing symptoms of pregnancy. Could I be pregnant?

ANY time there is penile insertion there is the risk of pregnancy. It is probably too early for conception to have occurred, definitely too early for you to be experiencing any symptoms due to pregnancy. You may be experiencing symptoms common to pregnancy, but they are not due to a pregnancy. But that doesn't mean you won't get pregnant from your encounter over the weekend.

The first manifestation of pregnancy is a missed period. So you need to wait 1-2 weeks after your next period is due. If it hasn't come by that time, you can start testing.

As Scott said, it's way too early to be experiencing pregnancy symptoms only a week after sexual intercourse. At this point you're not officially pregnant, sperm has to meet egg, egg has to descend and the egg has to attach. That doesn't happen instantly.

Could you be pregnant? Sure you can, you had sex, and any time you have sex, even with protection, pregnancy is possible. But at this point it's too early to tell.

Wait for your next period. If you miss it and you're normally regular, wait a week and test. If that test is negative, wait another week or two and test again if you still haven't gotten your period. If those tests are negative then wait for your next period. If you miss it, test again or get a blood test done.