The first two leaves on my chilli plant just shrivelled up and died - what caused this?

Could be snails, slugs, or other pests.

My first thought was overwatering, but it could be a surplus or a shortage of some mineral, too.

@lilikoi Cannot be as the plants are inside in my bedroom

When you say “the first two leaves,” do you mean the first pair that you saw when it sprouted? Or do you mean the first two “true leaves” that look like what chili plant leaves should look like?

If it’s the first two that it came with, you’re very likely okay. Those tend to dry up once the real leaves start coming and they don’t need the “beginner” leaves any more.

The yellowing of “true” leaves could be due to a deficiency of nitrogen or magnesium. No insect damage (nematodes, etc) seen? As @laureth asked, if these were the “sprout leaves”, they’ll fall off naturally.

Yeah they are the first leaves that appeared. Thanks guys.