Can Non Penetrative Sex Cause Pregnancy?

On the 21st of June I was over at my boyfriends. I am a virgin so I am very careful about sex. We started kissing and as far as we went was him rubbing my vagina, which i had pants and underwear on the WHOLE time. I'm not even sure if he had semen on his hands. I did get my period 3 days ago but it only lasted about 3 days and it was light. Then today I had a little bit of spotting but it stopped. Should I be worried?