Worried please help

My girlfriend and i just had sex with a condom on. Unfortunately the condom slipped off during sex and we didn't realize and i cam inside her. She is on the pill and has been for 5 months but she just had her period the week before and this is only her second day of taking the pill for this month. Should we go get the plan b pill or should we just wait it out? Please help im about to throw up from nervousness

[AUSTIN431]

if she taking it correctly then its still effective but its not 100% so taking a plan b pill just in case wouldn't hurt

[sweettaralove]

hi i just wanted to say that the plan b pill will work but if you waited to long it wont so i would say if she doesnt have her period on time i would call a doc . hope all goes good