Reina was not supposed to play at Marassi on Saturday night, but was a last-minute starter when Gianluigi Donnarumma felt ill during the warm-up.
“After the mistake in the first half, experience helped me to stay concentrated on every detail and not let my head slip away from the game," Reina told Milan TV, referring to gifting the opener to Lasse Schone.
“I am proud to see the reaction of the lads, especially after our defeat to Fiorentina and a bad first half here. We never gave up, tried to turn it around and at the end bring home three very important points.
“We knew at the break that a goal would get us back into it. We just had to keep going. It's not easy, as when there's a lack of confidence, it can feel like the football is burning and you don't want to be near it.
“Mistakes can happen, but we return home knowing we have given our all. The time will come when we feel more confident and the team will play better football."