What Causes Delayed Period After Taking I Pill?

my friends girl friend had period on 13th of may and they had unprotected sex on june 12th she has taken ipill in 1hr but she dint get hr periods till now is she pregnant? her age is 23 not married about to marry. and she is weak her weight is 45 she has irregular periods before will not eat food properly but she has a symptoms of getting periods, like body pains and pimples on face so what will you suggest madam? plz tell us what to do?