One day after my period ended I had sex with my boyfriend unprotected. Well actually, I gave him a few strokes and he cummed so fast (shaking my head) but claims that he pulled out. It is now 3 weeks after that has happened and I'm not sure if these are clear symptoms: Stomach pain, lower back pain, & sharp pain around my uterus/ovaries, and a sticky clear white-ish discharge. I haven't been having morning sickness and my breasts aren't sore.. could this just be all in my head? When is the right time to take a pregnancy test?

The symptoms you are experiencing are not only pregnancy symptoms, but also premenstruation symptoms.

Not everyone gets morning sickness or sore breasts.

Best time to test will be if you miss your next period.

Yes you need to wait till about one week after you have missed a period.

Can you be? Of course, since you had sex, even with protection, no form is 100 percent, but without protection it raises your chances