The Wales international admits he has struggled since the New Year.
Allen told Liverpoolfc.com: "I can feel it coming back. Sometimes I am too self-critical and I think there are elements to the quality of my game that are still improving. Hopefully between now and the end of the season, they will really come back.
"I am still young and I haven't had a long career, but if I am honest it was probably a vein of form that was something I hadn't had to deal with before. It wasn't the high levels I'd set myself, but I'm confident enough that it will come back.
"I've just kept working hard. Nothing changes - you just keep working hard and have faith things will improve."