Is it bad working out twice day?

I do Insanity in the early afternoon, lately I've just been so pumped and motivated so I do weights
late afternoon with my brothers.

The scale says I haven't lost weight, but in 2 weeks I feel thinner! I can actually start seeing definition
on my body. I eat very healthy, I honestly don't crave junk food. I won't lie though, if I want some ice cream I'll eat it. I don't deprive myself. I feel toner and stronger, but my body is looking thinner.
Hahaha I know I don't make sense
Anyways!

My question is, is working out twice a day bad?
My uncle who is not vwry fit himseld says its bad for your bones.
My brothers who are fit say it's not bad, just as long as I eat (healthy)
and drink lots of water, and if my body is tires or sore take a day off.

I think my brother is right?
But I want to get evweyone's oppinion