Q.What’s happening to my oregano and bell pepper?
About a week ago, my oregano (about 3 months old) was looking really nice. Then the leaves started to turn purple-brownish and so I harvested a good bunch of them. However, they just seem to look worse and worse every day. Attached below are pictures. Also there’s a weird thing growing on a newborn bell pepper, is it dangerous?

You may have both a fungus and pest issue going on.
The links below will help you.
Spider Mites will cause leaves to be
stippled with yellow; leaves may appear bronzed; webbing covering leaves; mites may be visible as tiny moving dots on the webs or underside of leaves,
Mint Rust Small, dusty, bright orange, yellow or brown pustules on undersides of leaves; new shoots may be pale and distorted; large areas of leaf tissue die and leaves may drop from plant.
https://www.gardeningknowhow.com/plant-problems/pests/insects/spider-mite-treatment.htm
https://www.gardeningknowhow.com/plant-problems/disease/learn-about-plant-rust-disease-and-rust-treatment.htm
https://www.gardeningknowhow.com/edible/vegetables/pepper/pepper-problems.htm