Feed CalMag and check your pH. I think she is stunted at the moment til you clear this issue up. Maybe even a molybdinum deficiency. I generally avoid actual soils these days, opting for coco, sphag, and perlite, because it holds pH better when using pH perfect nutes, where soil sometimes will fluctuate still.
You will also run into an issue if it gets rootbound later. It is a cutting it looks like, so I wonder how long did you let it root for before transplanting? I notice alot of my cuttings that I don't use a humidity dome for when I start them end up with deficiencies and look like this, because they never develop the rootmass required without the high humidity...next thing you know it is still standing and not quite "dead" but unable to live.