Are these leaves supposed to turn yellow!?

The leaves at the bottom of my plants are turning yellow at the tips. Can't really see in these pics, but I'm talking about the lowest leaves. (not the cotyledon) This is my 1st grow and I haven't started using nutes yet. I'm exactly 22 day's from germ to now. Any replies/help will be appreciated.

if your not talking about the rounded leaves, then no they are NOT supposed to turn yellow. i dont know why the ones at the bottom would be the ones turning yellow except maybe when your watering them or feeding them your hitting those leaves. when you water, move the plants to the side with ur hands carefully to make sure no water gets on any leaves. drops of water = magnifying glass, making the light burn the leaves easier. hope this helps

Thanks bruh!