David Cotterill grabbed the only goal of the game with the Swans task not helped by first half injuries to Darren Pratley and Ferrie Bodde.
Sousa said after the game “It is very important to keep on winning but it was a tough game for us today.
“The injuries made it difficult for us and we will have to see the results of scans before we know the extent of the injuries of Darren Pratley and Ferrie Bodde.
“Midfield could now be a problem for us in the coming matches and we may have to play different shapes to get over it as we have now lost two players in each of the last two games.
“We had a number of chances to score more goals, which would have relaxed us, but it never happened.
“We are looking to win games and be competitive but we may have to go into the loan market to cover all these injuries to our midfield players.”