No. Those tests measure a hormone produced during pregnancy, so taking it the day after sex won't tell you anything. (Read the info in the test.) If she's late for her next period, then you test.

Again, if the accident was recent, go to the doctor.

BTW, lots of things, including stress, can cause a woman to be irregular. If you guys are freaking out about this, then I wouldn't be surprised if she is late next month.

At the risk of sounding like a preachy old bit@h, how old are you guys?? I hope your gf already knows all this and you're just asking here so as not to stress her out. Accidents can and do happen, but that's no excuse for not being educated about all this stuff. Regardless, hope everything works out.

 

shuuuuuuu-uuuuuuuuuup

 

if you guys are at least college-age, just take her to campus health service center, they'll take good care of her for ya