Hi- It's still green, so it's highly likely it will survive. Was it the one labeled 'water soluble, instantly feeds, feed every 2 weeks'? Also, was it something that you just did once, or repeatedly applied? So that we can determine your next step. 

Yes that was the fertilizer I used. I applied it only once on April 16.  

If you only did it once, that long ago, while it is possible you burnt the roots, I would not expect the only cause to be your one time fertilizing, so I attached a link with possible problems that might occur, in case you are interested.

If you have loamy or clay soil type I would recommend not fertilizing it at all next year. If it was over fertilized, there may be residual nutrients bound to the soil over winter. If the shrub leafs out and does not look good next year, you can take pictures and update this question at that time.

As for future fertilizing, aim for something that either says hydrangea, ideally, or some sort of flowering shrub when shopping, as opposed to ‘flowers’. A slow-release, 12-4-8 fertilizer, or something similar, is probably going to be the best option as these are standard nutritional needs for gardens, as there should be enough phosphorous in the ground; unless a soil test told you otherwise. Incrediball is a smooth hydrangea which grows on the new wood, so you can prune it low to the ground in the fall or trim it down around the last frost date in spring.

https://extension.umn.edu/planting-and-growing-guides/pruning-hydrangeas-best-bloom#sources-3009710

https://extension.umd.edu/resource/hydrangea-identify-and-manage-problems/

https://extension.umd.edu/resource/pruning-hydrangeas/

https://ag.umass.edu/landscape/fact-sheets/growing-hydrangeas

Thank you so much!