It sounds like you have a nice setup there and your doing the right things for the sucess of your plant this winter.
Many plants which are purchased are greenhouse grown and once you get them home and indoors subtle changes will occur because the plant is now in less than ideal conditions, even with a grow type light.
Your plant could be exhibiting that.
I would not worry too much because many plants will look a little off when inside.
I posted a photo to show you what your leaves can look like in winter.
For me this is normal.
95% of my plants are not under lights and I water them like a cactus......less is more.
I use a razor knife to trim my leaves......one fast clean cut in downward fashion.
Do you have a led panel above your plant?
Weekly removal of leaves...
by
Hostafarian,
on Flickr