It doesn't look healthy. The new leaves are usually rusty red, changing to dark green as they mature. All new leaves should be bigger or same in size as previous.
Looks like it experiencing nutrient deficiency due to a weak or sick root system. I think your pots are too large for this size of sapling. I would recommend reporting it into a pot just a bit wider than a leaf crown. Deeper pots are better than wide in this case. Also, don't overwater, as well as don't let it completely dry out. I would put some used coffee grinds on top of the soil to effect the acidity. It works miracles for me.
Good luck and let us know if and when it improves.