Nerd

How did Fiona get pregnant? She was always super careful.

I have two questions... 1. When her boyfriend reminded her they had sex on Thursday too, the clock counter fast forwarded from 67 hours to 39 hours and she cursed. But, when they had done it on Thursday, why didn't she try to get the morning after pill back then? 2. Did she manage to swallow the pill in time? It is never made clear.