OPK help

Hi girls please help- I got my lot of opks on Sunday been testing since day 10 as I'm on a 28 day cycle and I got the flashing smiley face on Monday (Anzac day) BD that morning and I got my "non" flashing smiley yesterday and we didn't have sex yesterday  Should I be having BD today? Think I'm in with a chance? Also BD Friday and Saturday missed Sunday!