plan b

hi guys i’ve taken plan b before , this time idk what’s so different. i don’t track my ovulations or anything like that but i definitely should. i slept with this guy and he said he finished in me after the fact and that terrified me… i didn’t feel anything though and this was sunday at like 1am. i took a plan b sunday afternoon…. i feel NAUSEOUS. i’m kind of cramping ? i know the women in my family get super sick with hormones and especially during ovulations and i don’t know if i feel sick bc of that, bc of the plan b or bc i could be pregnant… please help.. i am terrified ..