Should I be worried?

So my brother has always been a smart kid. He doesn’t say much but he’s very smart. And recently I feel like something is wrong. He works at our family business that I had left for multiple reasons but one reason being that we were expected to work as family but not treated like family. Before he had this job he had another one and was fine. He liked it. He told my dad I don’t want anything to do with THC and don’t wanna work there. All of the sudden he’s working there as my replacement and you can tell he hates it. He doesn’t eat for 12 hours multiple days. He sleeps all the time. He now smokes because he felt obligated to because he works at a dispo. He’s not the same. I’m not against smoking THC. But I know he was completely against it and told my dad I don’t want to work there. Even the co workers tell us he doesn’t eat for 12 hours. And as his sister my love for him is very strong and I worry. He never texts or replies. Maybe it’s in my head. Maybe it’s not though.