Mel's men looked home and dry after their dramatic opening spell and might have gone even further ahead but for fine saves from visiting keeper David Marshall to deny Matej Vydra and Youssouf Mulumbu.
But despite sliding deeper into the relegation dogfight, Mel insisted the circumstances of the result would not impinge on his side's survival prospects.
"We made the wrong decision when we were 3-2 up with 30 seconds to go, and that should have been the end of it," said the Spaniard.
"The changing room is quite bad but they will see tomorrow that we played a good game and the result should have been a better one for us.
"Simply by showing the players the video of the first half, and showing them how well they played, they will be able to see how capable they are of playing well."