Leaves bending down

Here is what you need to do; check your plants every 4-6 hours if possible. Since you're growing indoors and your light on/off could be opposite of the sunlight outdoors, your plants will have a time where they will sleep, and a time when they're maximizing photosynthesis and praying. Once you know when your plants do both of these, THEN if you see an anomaly (something out of the norm) then dig in further to find the issue. But as others have stated, if you haven't under or over watered and it's drooping, odds are it's simply resting.

I think your okay. They tend to droop down abit on lights off so if you've taken the picture as soon as the mights turn on they may look like this. Give it a week and see how it is. At this stage I'd probs be watering only like 200ml of water every 3 days or so. Let it dry out before you water again, but try keep it a consistent pattern.

This is exactly how some plants grow........there is no real problem.