SirGideon

Really hard to diagnose. At first i was sure it was lack of iron, but iron deficient plants usually start to yellow from leaf stem to tip. Yours are yellowing tip to stem. Nitrogen defecient leaves usuallu yellow from tip to stem but they typically yellow evenly without leaving any green leaf veins. And the yellow tends to eventually crisp up, turn brown and die. Your leaves are yellowing tip to stem, leaving green leaf veins. What most closely resembles what i see your leaves doing, based on my research, is Sulphur deficiency. Here is a link for you to explore that i think will help. https://www.zamnesia.com/grow-weed/499-sulphur-deficiency-cannabis-plants

Bud sites at only Week 3?! That's pretty insane. Good work, buddy!