If you got your period after having sex, that should mean that you aren't pregnant... unless it wasn't actual period, but some sort of spotting. Were you regular before, and June 17 was a pretty normal date? Then having sex on the 15th hasn't done anything, since it was nowhere close to ovulation. If you want to be certain, take a planned interruption - as if you end the round, doing 3 days of VLCD without HCG, so the hcg has time to leave your body... then test again. But it is pretty common to have a messed-up cycle on HCG - I have been all over the place in terms of spotting and timing. And I know I am *not* pregnant.