[Arubalisa]

I would think that if you believe you will be freaked out it is because of the mask and a feeling of claustrophobia? If so, snorkeling may never be an option. I know that has been the experience for my FIL.

Your lesson is in a swimming pool? Stay at the shallow end and not much bad could happen there as long as you can pop your head above the surface and spit out the snorkel tube.

You will be fine Michelle, we are all backing you!