Call your contractor or tile installer back in for suggestions. Do not wait. Do it right away.

That is beautiful glass. Just had the same thing happen to me in the kitchen. My decorative tile was $145.00 a sf. Thankfully, I only lost three sf of those - OH and the other 800 dollars in the body tile plus hundreds in labor. I am so sorry! I feel your pain. I fired the guy and swore at him with my best Cleveland accent (though I live in Phoenix). Hacked all the tile off the walls, ripped down the cement board, and I am back to the studs. It helped to lower my blood pressure, and I can look at the studs with much better aplomb than that HORRID POS TILE WORK. At any rate, I certainly do hope you have recourse. That was simply unacceptable work in your shower. Doofuses.

Currently having the same problem same type of tile also ,I think entire will have to be torn out and redone

Gotta love resurrections from the deep.

Creative writing at its finest . Well said Oliviag55