Fridge isn’t cooling milk

I was pumping for my baby but now I started breastfeeding (been 2 days) but I’m scared he’s not getting enough. He’s peeing his diapers but about halfway through. The other concern I have is that I was pumping but I don’t think my fridge is working because the milk doesn’t feel as cold as other times. (My other milk is still frozen so maybe i’m being paranoid? It has leaked some times this week though) I don’t want to give him milk that doesn’t work but I also don’t want him to not get enough. I was thinking perhaps pumping before he wakes to have it ready but sometimes he takes longer to sleep so i wouldn’t want it to go to waste either. Should I keep trying to breastfeed or pump before i think he’ll wake? I can’t track his weight right now but what’s a sign that I need to supplement? And how long does it take to know you need to supplement?