"It's becoming crucial now that we've got to go home and we've got to win," Flanagan said.
"There's no beating around the bush any more."
Cronulla were expected to start the season strongly with the recruitment of former Dally M medallist Ben Barba and former Bulldogs captain Michael Ennis.
Flanagan said the newcomers were taking time to gel, and said those already at the club were still bearing the scars of a disastrous 2014 season.
Flanagan was unable to coach, suspended by ASADA following the 2013 supplements scandal, then interim coach Peter Sharp stepped down.
Star player Todd Carney was sacked and they collected the wooden spoon.
"They had a pretty tough year last year, so there's a few scars there," Flanagan said.
"We need to build a bit of confidence and with those new boys coming into the club we need a bit of cohesion and they are both missing at the moment.
"We're working really hard and the group's really solid so we'll just keep chipping away."
In one positive for the Sharks, Kangaroo Luke Lewis made a successful return following knee surgery in February, playing about 25 minutes against the Storm.
Meanwhile, in the day's other game, the St George Illawarra Dragons clawed back an early 18-point deficit against Canberra at GIO Stadium to record their first win of the season.
During the dramatic come-from-behind 22-20 victory, Dragons fans who spent the first half booing their own players all of a sudden had something to cheer about.
The win follows two poor losses for the club, which triggered mass social media calls for CEO Peter Doust to be sacked under the Twitter campaign #SaveOurSaints.
However, coach Paul McGregor called for fans to have patience after the win in Canberra on Saturday.
"You can understand the fans' disappointment," McGregor said. "They want the side to win. But they shouldn't think for one minute of every day that we are not trying to please them. We are working around the clock to please them.
"We want to do that but it takes time. I hope they understand that and I hope they can be patient."
Dragons captain Jason Nightingale admitted his side's first two losses of the year were "pretty dismal".
"But we were always confident we could put a smile on fans' faces," he said.
"We're going to do everything we can to improve and ensure we don't put ourselves in situations like we did in the first 15 minutes of today's game."
- AAP