New to LPS.. Check out my swollen trachyphyllia?!?

so this trachy, or wellso or open brain.. whatev you want to call it decided to puff up like a giant baloon today.. he has been in the tank now for a week or two at least... im new to this and i searched everywhere but could not find any info on swelling up like so.. i did read they will swell but its almost to the extreme here,, is this normal? every pic i could find looks like how he did the whole time i had him previously ( yes its a him now..) if it was a pimple i would of already popped it... but since he was more expensive than a pimple. i figured i would ask you all if this is good, bad, normal, or what?!


here are two pics of the swollen member... and the last ones were a few days prior when i thought he was normal.. currently in my moon lights he is actually even bigger!!! i guess i can only see what goes on tomorrow..





heres a pic.. sorry its off my cell phone..








another













and what i presumed to be normal a few days before.. just happened to snap a pic of the tank...