Kirwan has scored in every game this season, which has propelled him up the national statsheet.
After going down early, Penn State rallied back with four unanswered goals to secure the win.
"We're a good group that is going to fight all year. We're going to stay in the fight."
Three buzzer-beating goals pulled the Nittany Lions through a tough road match.
"I think it's going to be great for us. I think it's going to really gel us as a team."
The Nittany Lions survived a tense battle on the road to stay unbeaten through 11 games.