Alright thanks that helps a bunch!
Today is the 25th. So about 4 days ago, you had sex. You wouldn't be experiencing any pregnancy symptoms right now, since if the egg was fertilized it would just now be implanting into your uterus.
You don't being to have pregnancy symptoms immediately after having sex, and stomach pains and side and pack pains aren't symptoms of pregnancy.
Wait until your period is due, and test. Obviously you could be pregnant by that time.