Its this normal? (yellow leafs down)

cotyledons can be sacrificied. This is a sign ot start fertilizing, if you have not, yet. If in soil, start slowly and around the near vicinity of plant... stick to water-only around outside ... wet/dry cycle.. allow top layer to dry before irrigating again.. maybe up to 1/2" this early.. and 1" later. the idea of teh fertilizing near plant and not at outer areas is to avoid buildup. the soil will have nutes in it. there are no roots there. so, in time it would become toxic. If that's coco, it should be buffered and basically the same idea.. becareful of over fertilizing where no roots exist, yet.