Smith, who went home to Texas over the weekend, said he felt great.
"I'm happy to be back with the guys, laughing and sharing the same passion and working together," Smith said. "It was exciting for me."
Smith, who missed several games last season after suffering a concussion, had to watch the Carolina game with other injured players.
"Through your tribulations you learn patience," Smith said. "Through your patience you learn experience. Through experience you learn hope. Just having that hope that one day I'll be able to get back out there. I just thank God for the opportunity just to be a part of this team. I was wishing I could have helped."
The Rams have had some struggles with head injuries this season. Tight end Darcy Johnson was put on injured reserve because of a concussion and defensive tackle Clifton Ryan was put on injured reserve after missing several weeks with migraine headaches.
Johnson was in the locker room following Monday's practice and he and Smith were able to talk for a few minutes about their concussions and what they were dealing with.
After missing six games last season with his first concussion, Smith knows that the time for recovery varies.
"It's one of those deals," he said. "You can't predict them, you just have to deal with them."