Record signing Bent was axed from the starting line-up against the Baggies, with Lambert preferring Gabriel Agbonlahor and Christian Benteke in his starting line-up. Bent was introduced midway through the second half and earned Villa a point with an 80th-minute close-range effort.
But, when asked if Bent was upset, Lambert said: "No, he was great. There was no problem. I just named the team and that's the team I picked."
The England striker admitted it has been a difficult couple of weeks having also lost his England spot and the Villa captaincy, to Ron Vlaar.
Lambert added: "Everyone is as important as anyone else. I explained the captaincy thing was to do (let him focus on) what he did there - to score. That's the only reason I did it.
"I need everyone. If we can keep the collective thing and have the crowd with us, we'll be fine."
Lambert was full of praise for the way his players responded to going behind to a Shane Long goal, particularly after playing 120 minutes against Manchester City in the Capital One Cup in midweek.
He said: "I thought the response was great, especially after playing 120 minutes on Tuesday. It was a big, big ask but the response was excellent."
Baggies boss Steve Clarke was disappointed to concede a late goal but hailed a top-drawer performance from Ben Foster. The former England goalkeeper bounced back from his poor performance against Liverpool in midweek with several fine saves.
"Having been in that position I'm a little bit disappointed we didn't go on and win it," Clarke said. "But Ben Foster was excellent. I said the other night when he made the mistakes there was nothing to worry about - and he proved that. He's a top goalkeeper and made one save in the first half off the deflected shot which was unbelievable."