First time grower - Overwatering / too much light?

I bet that tip is warmer than the air around it which indicates no transpiration but new growth looks OK. You need moderate temp and high RH at this stage.

Heat stress will curl your edges of leaves upwards not downwards down ward drooping can be normal if the lights have only just come on but if they have been on for a while its most likely over watering. Light stress will cause your leves to bleach the colour of the light most of the time its bright white so really easy to spot you will notice the same effect when buds get too close to the light they will bleach white like an albino bud lol looks cool and doesnt effect the flower in anyway just looks strange lol but yeah just let her dry out shes not that old she doesnt need much at this stage try to only water around the base of the plant not saturate the whole medium :) Best of luck shes looing healthy anyway :)