What is this growing?

[Hiimscott]

Hey guys, I'm new to salt water tanks, I bought a Duncan Coral frag online about 4 weeks ago.
In that time this little growth has started to grow next to the main drag. It has been like this for about 2 weeks, originally I thought it was a new head growing but I've read that new heads should take about a week to grow. This hasn't seemed to change in the last week. It just grew on half of the 'stem'? The other side looks like basic rock. I'm not sure of all the technical terms of each part of a coral, sorry

 

[ISpeakForTheSeas]

Can you get some pics of it under white light? Blue light makes ID’ing difficult.

 

[Hiimscott]

Can you get some pics of it under white light? Blue light makes ID’ing difficult.

 

[ISpeakForTheSeas]

I'm not sure what it is, so hopefully someone who does will chime in for you here.