am i just freaking out or what?

So i had protected sex 2 1/2 weeks ago and my boyfriend pulled out way before he came. I'm not on the pill and that makes me always think i'm pregant when i get the slightest of symptoms. My boobs really hurt and they usually do before i get my period (which should be next week) but not this bad. Also i am applying to college right now so i'm really stressed and tired. What are the real chances that I actually am pregnant?