Green Belt

Congratulations. Speed is a factor in kata quite often. There are two reasons for the forms moving quickly in my experience:

1) Nerves (to be understood when going up in rank)

2) Not knowing the form and hoping no one catches the parts you are unsure of (you in general)

This is why it is always a good reason to move slow through forms in practice. Do it with breathing. Hell, even at 2nd Dan, I find myself cranking through some of my forms in demonstrations because of nerves. Once I catch myself, I can slow myself down. But this is something in all of us that can be worked out over time.

Again, congratulations on your advancement and keep working hard.