The Reds missed out on European glory at the last hurdle on Saturday night, as they fell to a 3-1 defeat at the hands of La Liga giants Real Madrid, who retained the title for a third consecutive season.
Despite reaching the Champions League final, Lovren believes that his side will perform even better in the upcoming season in August.
"I'm proud of the team, I'm proud of the players. They gave everything," said the Croatian international.
"I'm proud of the fans who travelled such a long way to support us. I promise that next year we will come back even stronger because I feel this team is growing every day. We beat the best teams in Europe. We beat Man City, who had a fantastic season in the Premier League. We showed again that Real Madrid respected us in some moments - they were defending quite deep. We need to find the positives. The manager is always positive. At the end, we will grow and I believe in this team that we can do it again next year.
"It was also a big point when [Mohammed Salah] was injured - it was a big change for us. Mo is one of the most important players for us and it's not the same when you don't have him on the pitch The mindset is totally different when you have him on the pitch. It was difficult to accept that we, again, had such an unlucky moment with so many injuries.
"I cannot believe we had so many injuries this season. I hope that's he's fit for the World Cup and it's nothing too serious. It's easy to blame someone [for the defeat], but we are in the same ship together and everyone gave [Karius] the best words that they can. He will come back strong. Don't make massive stories about that. Of course it's big because it's a final, but everyone makes mistakes."
Despite missing out on the trophy, Liverpool still won €15.5m (£13.6) for reaching the final of the Champions League.