Am I Missing Something?

Julia

So the past 3 months I have ovulated around CD 18 or CD19. Today is Cycle day 18 for me. The pictures are (in order) CD 15, 16, 17, and then today - CD 18.

Am I just getting close? Other than CD 16 they all look roughly the same - not quite positive, but not my typical super faint line I get early in my cycle.