Ovulation question

As of August I stopped bc.

My cycle the first 2 months were the same amount of time. My third month was a week longer, and last month was an extra day more than the third month.

So obviously my body is adjusting to natural still, so I’m wondering just how accurate the app could be on my ovulation.

We had an oops where he was so into it he forgot to pull out lol so I wiggled off but he still was able to get the first shot inside me.

According to the app I was at 33% yesterday so I’m wondering if plan b would be worth while. I’m nearly 24 hours into the 72 hour window so I’m thinking it’s not going to do anything.

I’ll be messing my cycle up for nothing pretty much.

Am I wrong?