Is this normal or am I preganet?

Patient: 3 weeks ago i had unprotected sex so i when out and bought a plan b pill a week after i had what i thought was my period and i got it a week before,it lasted for 4 days,days after that i been feeling weird,i get so hungry when before i didnt,and very tired even if Ive had plenty of rest and nauseous.just yesterday I went out to get ice cream becuase I was craving rockyroad ice cream few mintues later after eating the icecream i felt so sick and i threw up the whole icecream is this just a side affect form the plan b pill or am i preganet?