Ovulation Timing Question

Ashley • Emma born August 2010. James stillborn January 2015. Sarah born January 2017.
Yesterday in the morning and evening I had obvious positive OPKs. Today I'm back to a faint (negative) test line. It's only been 24 hours. Does that mean I've already ovulated (yesterday) or that I'm ovulating today? Pics below for reference. Trying to figure out when I'm starting the 2WW.