Is Pregnancy Possible After Taking Next Choice Followed By Non-penetrative Sex?

Hi on saturday night i had sex but with protection and non penetrative. but i was worried when he got off me that some of his cum got on me from the condom. i took next choice tuesday at 4 o clock in the afternoon and another 12 hours later. should i be worried? i'm expected to start my period between the 18th and 20th of this month.