However, the Italian striker smashed his effort into the stands and, thanks to Henderson's earlier goal, the Reds ended the Group A clash as 1-0 winners.
"My heart was in my mouth at that point," the 22-year-old told the club's official website.
"I honestly thought, 'here we go again', but credit to the guys, I think we looked comfortable for the majority of the game. It's always tough away from home when you have a 1-0 lead."
The result, twinned with Young Boys' 3-1 victory against Anzhi Makhachkala, saw Brendan Rodgers' men qualify for the next stage as group winners.
The former Swansea man, signed in the summer, was delighted that his new team managed to clinch top spot, while he expressed his joy that the club will still be competing in Europe after the Christmas period.
|REDS TO GO ALL THE WAY|
|14/1||Liverpool are 14/1 with bet365 to win the Europa League this season|
"It's a great feeling to know we'll be playing European football in the new year. European football is a new experience for me and I want to keep that going - it's as simple as that.
"As a player, you worry that this might be the last game in the competition.
"So that gave us that added incentive to get through and the added incentive to make sure that our name is in the hat for the draw for the next round."
The midfielder, who represented Team GB at the Olympics, did however warn against complacency and suggested that although they were dominant they should have won by a bigger scoreline.
"You can always look back on games and think we could have done a bit more and killed the game a little bit earlier," he continued.
"But aside from their chance right at the death, I don't think they caused us too many problems. Yes it could have been more but the main thing is that we got the three points."