You really can't go by what symptoms you experience to determin weather you're pregnant or not.
Some woman have some symptoms and some woman have no signs at all.
Just like morning sickness. . . I didn't have it threw my entire pregnancy but some woman did.
I wouldn't base being pregnant or not on the symptoms you believe are pregnancy based.
Really you should take an hpt if you think you may be pregnant and see a doctor. Also if your scared about the fainting episode then still see your doctor and fill them in on what's going on.
Good luck and I hope you fel better and get some questions answered.
.Jenn