Help with yellowing leaves (from top down)

I’ve been trying my luck indoors, with a couple of sugar rush peach peppers this winter. The plants have been frowning well, and started to flower.

This one was recently transplanted into a bigger pot, about two weeks ago. Now, the leaves are yellowing from the top, spreading down.

Extra info: I have been watering every other day, adding about 200-250ml. I may have packed the soil a little tightly in the pot, and don’t see any water come out the drainage holes. I have not used any fertilizer (aside from what’s in the fresh potting soil) to date.