Drooping, withering and dropping chili leaves?

Hello,

I have gotten this chili plant not too long ago (the 6th of August) and it was looking lovely with beautiful leaves and fruit. However, now after having it for 6 days, the leaves are withering, wilting, curling, and falling off. The fruit is also wrinkling up and some are starting to point down, while before they were all pointing up. The chili plant is a Acapulco Purple.

Attached, I have 4 photos: one of the plant in general, one of the leaves, one of the fruit, and one of the roots and soil. To me, the roots look slightly constricted, though I didn't think that it was much of a problem, since it would take more than 6 days for them to get root bound. Should I transplant it to a bigger container?

I put the plant in a shaded, though warm spot in my apartment, and keep it out of direct sunlight, as the room is bright as is.

Thank you very much for the help,
Annie S

 

To me it looks like over-watered. It is root bound, too, it should be in a bigger pot long time ago.