Ovulation right after period?

Cris • 2👶🏻 💙, 1 👶🤰💖 (IUI)

My AF came 2 days late on 12/11 and ended early on 12/15 (yesterday), I saw hint of blood. Regardless, I took an ovulation test and got negative yesterday.

Today, I took another one and it says I’m at my high fertility phase already. The smiley face is flashing. This actually happened to me last month as well. I ended up having high LH level 2 times a month. Is anyone else experiencing this? Is this normal?