timing of your period

[stilltired]

I really need to get an answer to this!  Most people say a hpt is more accurate if you wait a week after your missed period to test.  But what if your missed period is only a few days to a week after intercourse?  Is that too soon to test and you have to wait for a week after your NEXT missed period?  

For instance, can anyone answer these specific scenarios:
if you have unprotected sex today and your period is supposed to start tomorrow and never comes, when can you test?  
If you have unprotected sex today and your period is supposed to start in exactly a week but never comes, when can you test?  
OR, if you know you're definitely not pregnant (because you haven't had intercourse for a while) but your period is already a day or so late and you have unprotected sex and then don't get a period within the next few weeks, when can you test and be fairly confident in the results?

(I know, odds are lower for getting pregnant around the time of your period, but not everyone ovulates around day 14, and I don't have a clue when I ovulate--plus my cycle is probably off because of getting off the pill, so I'm worried that it's entirely possible I ovulated in October around the time of intercourse, which was at least 21 days after the start of my September period but might have been closer to 28 days, and I have not had a period since September.  Again, could be from getting off the pill.)

[stilltired]

Thanks!  I took another First Response today with first morning urine--it's 25 days after unprotected sex.  It was negative.  I still haven't had a period, and I feel extremely bloated in my abdomen.  

[alaysha]

You can test 2-3 weeks after unprotected sex and by then you should get an accurate answer.