Rovers opened the new campaign with a 2-1 defeat to AFC Wimbledon as disrupted preparations and injuries took their toll on the performance.
Wellens handed out ten debuts on Saturday with the side showing a lack of cohesion and the need for development.
And he believes there will be more tough days to come as the redevelopment of the team continues, but will remain encouraged as long as there progress.
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“I’m really disappointed but we know where we are,” he said. “It’s a rebuild and there are going to be times when we have to suffer.
“As long as we suffer together and we’re going in the same direction, I am good with that. But we do need to improve and we need to get our injured players back.
“At times we could be more explosive in the final third. It was a bit slow, slow. We had opportunities when we got to the byline and it was a little bit tentative instead of really being positive and trying to score goals.”
The Rovers boss believes the most significant progress will come when injured players return to action and others are up to speed.
“The biggest thing will be when we get all our players back,” he said.
“I think at times, Wimbledon are a decent League One team but when they got it into their front players they were a threat.
“When we got it into our front players it broke down too many times. We looked a bit laboured rather than being really positive. I think their front players were a threat, mainly because of us giving the ball away in the wrong areas.
“If you take Fej Okenabirhie, Jon Taylor and Jordy Hiwula out, you’re going to suffer.
“But we can’t make that an excuse because we don’t have them for the foreseeable future and people need to step up.
“We know where we are, we just need to stay patient. We’re going to suffer at times but we need to come in Monday morning and prepare well to try to get ready for Tuesday.”