Gallagher struck twice in the team’s 3-1 win at Middlesbrough last Monday and the striker, who returned to the club midway through the season after a loan spell at MK Dons, is confident of adding further goals in the coming weeks.
“I've missed that feeling a bit lately, so to get the first one was amazing for me and then to top it off with the second, which sealed the game as well, you could sort of tell by the celebration from everyone that it was a great day.
“I think everyone else could sort of feel my frustration with myself from not scoring, so once it went in seeing Harry Reed and people like that just jumping at me was nice.
“It's a case of relief and now I've got more self-belief and more confidence going into the next few games, so hopefully it will mean more goals.”
The 20 year-old has re-joins the U21s as they seek a move away from the relegation zone, with Gallagher eager to improve the team’s league position.
“All of a sudden it seems like we're in a bit of a relegation battle,” he acknowledged. “That's sort of come upon us quite quick and now it's not just a case of getting the performances, but we need to get three points.
“The most important thing is that we stay up, but to stay up we have to win, and to win we have to score goals. That's going to be my main objective, to score as many as I can coming into the end of the season.
“We've missed that winning feeling for a little while, so during this week we've had a much better feel around everyone and you can tell we're all looking forward to the Liverpool game.”
Saints head to Merseyside on Sunday looking to build on their first win of the calendar year, and Gallagher expects a good game against the Reds who beat them 2-1 at Staplewood in January.
“It's going to be a bit different than Middlesbrough and Leicester,” Gallagher explained. “Both teams are going to look to keep the ball and move it around and switch sides, but it's definitely more of a game that will suit us I think, getting the ball down and looking to play between them.
“The last game when we played them at home we felt that we should have got more from the game and we should have beaten them, so we definitely want to go there and get three points.”