Indoor gardens have no predators, stable warmth, and a buffet. When something gets in, it multiplies fast. The rule for all three of the big invaders: treat the day you find them, because every one of them is a week away from being ten times worse.
Spider mites: the tent killer
ID: tiny specks on leaf undersides, pinprick white/yellow stippling on top of leaves. Fine webbing between buds means severe infestation. Confirm with a loupe: tiny moving dots, often two-spotted.