It's possible that you o'd a day later, on the rise. I've o'd early in the morning and that morning there's a rise in temps.
I haven't heard that a long lp isn't good. According to text books and some doctors' opinions, 14 is normal and everyone has 28 day cycles. Something like that anyways.

Too long is better than too short, IMO.
I wouldn't be too concerned right now. It looks like you o'd and the B6 helped out your LP. Technically, the only proof of O is pg, but we just have to assume your temp shift was caused by O.

I've had my share of crazy cycles so I completely understand.