Understanding Early Pregnancy Symptoms & Period Changes

Question
Hi There!

I really appreciate you taking the time to answer my question!

My husband and I have recently decided to start a family - this month.  As of May we had been using the withdrawal method as our means of protection, and my period arrived on May 22 - 26 as it should have.  We didn't calculate ovulation or anything for this mounth,we just stopped withdrawing and carried on as usual.  My body started acting up about a week ago with some cramping (like menstrual cramps, but with out my period...) soar swollen breasts, frequent urination, and increased appetite.  Even though my period isn't due until the 23ish of June (this month)  I decided to take a pregnancy test (Clear Blue) on the 16th, and both of them ( I took two at two different times that day)  came up positive,  fairly faint, but the plus sign was there.  I phoned the Unipath people and they said its unlikely to be a false positive and showed faintly because of it being early.  I know that the test detects the hormones in your urine and that there shouldn't be enough to detect until the day you miss your period...  I was wondering why you thought it did show up as a postive so early?  Is it possible that we conceived sometime in May, and that I got my period anyway?  It was no lighter or heavier than usual.  Thanks in advance for your thoughts!
Jenn

Answer
I agree with the "Unipath" people, even though I don't know who they are.
Pregnacy test can detect earlier than they say on the box, they tell you the first day of your missed period or women would take them the day after sex!  
Good luck and Congrats!