Which day should be 1 DPO?

Question

DPO?" /> I used OPKs in the morning only and thought I would get my positive cd14 because of my obvious temp drop then but didn't until the next day. Should I count dpo based on the temp drop or the positive opk? If going by the opk, my luteal phase is pretty short, which worries me! And I know my post ovulation temps are crazy as I had a weird schedule during that time and wasn't consistent with time.