When I dug the hole for my blueberry bush I only filled the bottom with ericaceous compost placed the bush on top then filled the sides with the soil I dug out the garden to make the hole, is this a problem ?

Welcome to NGA @Jmarsh31

The main consideration is the pH of your soil; blueberries need a pH of around 4.0 to 5.3. I learned this the hard way, when my plants came to life in the spring with bright yellow leaves (not a good look for blueberries or most any other plant)

Do you know what the pH of your garden soil is? If not, I would suggest having it tested, you may need to add some soil sulfur to acidify your soil.

I had to look up ericaceous compost - it has a pH of 4 - 5. That would be a good pH for your blueberries but I think I would have mixed a LOT of it into all the soil. Roots grow mostly sideways.