It's looking fine, just a pit pale. Could have a minor nutrient issue. Are there drainage holes on the bottom of that cup? Topping is a good idea, it will make it branch out.
They look pretty healthy. It looks like a tiny bit of ph flux, but you say your ph hasn't changed. Have you noticed more spots appear since you changed the water?
Get the temps in range if you can. You can add extra perlite to the mix to lighten it when you transplant, it will make it hard to over water. They look pretty healthy.
It looks like the leaves are clawing a bit, do you monitor the nutrient levels? It doesn't seem unhealthy otherwise, but it's a really small plant to be putting to flower. Are you sure it's not the color of the hps light that's making it look unhealthy to you?
I go from 105w cfl's in veg to...
If you want to check the nutrient level collect some of the run off water next time you water and measure it with a ppm pen. That's what I'd do. Check the ph as well.
Hey, I use a 45x magnifying lens to check the glands. As soon as they start to bend over I harvest around then, that is considered peak potency. Letting them go longer will produce a more sedative effect, which some people prefer.