well,it all depends on what day u had intercourse.10th -18th day of a28day cycle is considered the fertile period.outside this ur safe.but if u figure out the day u ovulated,then 2-3days after that is safe.
Take a test and hopefully you get the results you want
Well honestly, I haven't really been that stressed at all compared to what I used to be. I wasn't stressing on this issue because I had convinced myself there was no way I was pregnant and my boyfriend confronted me when I told him my period was supposed to start on Wednesday and he said oh yeah you we finally get to tell if your pregnant or not and I was like oh damn...and then I didn't start and still haven't and now I'm a lil worried but still not like freaking out bad or nothing. I mean if I am there is things I could do if I really didn't want to keep it, but I love babies and kids so I'd have to keep it.
Make sure you are under no stress as that can also delay your period. I have a very regular period but mine was 7days late due to the stress I was under (lost my best friend through a car accident).