Do you feel sperm inside you

Carron
Me and mybf were having unprotected sex and herold me he was about to nut and i jumped up and as soon as i got up ge nutted but we thought he nutted at first but then he says i missed it by a split second .. And there was nothing on me or coming out of me and when itried to push it out nothing was there . So should i be scared and buy pan b or just not worry ?