We live in NW Connecticut...Zone 5a
We moved into our home in the fall of 2014. We had beautiful, but overgrown pool area. It had forsythia as the dominant plant. We cleaned/cleaned it up, moved the pool equip behind our shed, and after looking through tons of Pinterest images and magazines we found our inspiration in the following photo:

We planted mature shrub form peegees in the spring of 2015. We wanted big beautiful bush forms around the pool. We thought the ones that were planted looked a bit like tree forms, but we were told that we could just prune them and make them bushier (knock back the central, long stems).

We have since stopped worrying about the whole bush vs tree form thing. We love them and here is what they looked like last summer

We never did any serious pruning. I went in there an removed what I thought was some dead branches. In the meantime, we bought some additional peegees for other places on the property. We didn't make the rookie mistake of buying mature plants as we realize how fast and lush these shrubs can get. Whenever I asked our trusted nursery owner about care he would say "just mow them down to the ground in early spring...give em a haircut".
Since our pool hydrangeas are so mature and woody this did not make sense to me. So in mid-April (which was still chilly up here ...no buds yet) I took off every thing on the plant except for the big wood stems (which I cut to a height of 3 feet). This is what it looks like now...

I'm sure we overdid it. Will we get back the growth that we had last year? Will there be any flowers this year? Did we cut back too much?
There is new growth so I'm sure the plants are fine. Should I be removing any leaves shoots at this point? My instinct was to remove any shoots / leaves / buds that were heading back across the interior. But perhaps our severe haircut necessitates leaving them alone.

Thanks so much for reading! I appreciate any advice and input that would help us maintain these guys and get them to grow into the lovely, huge bushes we have in our inspiration photo.
(the fence was an addition that the town required after moving the pool equipment)