kinda of unprotected? definitely paranoid.

Okayyy need advice
So had sex today without a condom and my boyfriend came inside me
I am on the pill, I have taken it on time for ages the only factor is that 8 days ago I had diarrhoea, charming i know. But that should be fine because you're protected after 7 days of the pill, right??
So being new to all this we are just a bit paranoid of being pregnant, also because my period trackers says I'm 'fertile' right now 
Sooo is there any chance I'm pregnant guys?????? Should I get plan B just in case?