Another dumb question!

[aragornlover8]

Okay, so I got a positive opk last night on 04/13 (digital smiley face) and another one this morning on 04/14 (even though I know I don't really need to keep testing). This was after a bit of spotting I had yesterday, which is pretty indicative of ov for me. Then I tested again tonight and no smiley. Is it okay to treat the 14th as a tentative ov date? To base my testing date and dpo off of?

I'm considering doing a preliminary test on April 21st, considering my first calculated luteal phase off of the pill was ten days long. This seem reasonable?