A state of mind
A state of mind is when you're so focused on something it's like your brain is on fire and your thoughts are screaming at you to just stop and take a breath.
I was in a state of mind during my math test because I was so focused on getting the right answer that I didn’t even notice the time.
My sister was in a state of mind during her science project because she was so obsessed with getting it perfect that she forgot to eat.
My dog was in a state of mind because he was so focused on catching the ball that he didn’t even notice the cat was watching him.