Tiara,
You may not see any symptoms even if you are pregnant. And even if you do have symptoms.
You'll need to wait 14 days from intercourse and take a home pregnancy test to be sure (The tests *can* show pregnancy as early as 10 days, but if you did get pregnant, you may have had implantation later than the day of intercourse.)
If you don't get your period by 28 days after your last period started, take another test, just to be 100% sure. If that test doesn't pick up anything, then you can be sure that you didn't get pregnant (that day).
If you are having sex, I strongly recommend that you not rely exclusively on condoms - although they are the only method that lowers the risk of sexually transmitted diseases. Condoms do break on occasion. For best results, use a hormonal method such as the pill, the patch, the ring, norplant, or depo-provera shots and ALWAYS use condoms as well, unless you are 100% certain that you and your partner are monogymous and you've both been screened for sexually transmitted diseases.