Can Trumpet Corals bruise?

[dbraun15]

I purchase a small piece of neon green trumpet coral a couple days ago--I was "a little rough" trying to get it into a hole in LR and was wondering if they bruise--there are a few small brown spots on the heads and am wondering if that's it or is there something wrong? It finally opened this morning and seems otherwise healthy--thanks for the help/advice--BTW trate 0, ammonia 0, ph 8.3, temp 80-82 F, it is in the middle of a nano cube 24 with stock lighting