What Does No Fetus Growth During Sonography Mean?

had my last period on 23/3. had unprotected sex on 22/4. took deviry 10mg (1-0-1) for 5days. have not yet got my periods. pregnancy test is positive(one line is faded). did a sonography that shows no fetus growth. what could be the problem. im experiencing pains in lower abdomen and also a little vomiting feeling.