helpppl!!

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​i need a little help everyone.. december 26-28 i had my period. it was only 3 days, which is a little short for me, i usually last 4-5 days.

on january 1 & 2 i had unprotected sex (i’m on the pill and he pulled out)

now yesterday january 6 i had realized i had forgotten to take my pill the night before so i took it around 9:30 am, well later that day i stared cramping and i had light but noticeable spotting. could anyone explain to me what’s going on?