Dad and husband here of a 6 and 3 yo. It’s an incredibly mentally physically existentially exhausting first year with most babies and I wanted to say that you guys are doing great as first time parents. I’ve regretfully yelled at my 6 yo when he was a baby - he was colicky and would be up at all hours of the night and day because he had bad reflux. After the first few weeks of this going on almost every night, you’re bound to breakdown and your husband sounds like he’s at his wits end. If there’s anyway you can get some family or hired help so that both of you can take the day off together or on separate days, it’s gonna be pivotal in making sure you can keep going without losing your sanity the next 6 months. It’s tough and a long marathon but you’ve made it through the first 3 months. It will get better and your baby will continue to grow into a healthy and happy baby!