Warning poopy photo

Hi guys, I’m needing bit of guidance here. My baby is 2 weeks and two days old today. Earlier this week we decide to switch him onto Enfamil from similac advance pro for a few days and I completely regret it or not sure if this is what changed my baby’s poop or not. Just seems like his pooped changed in the same timing we switch his formula. So we went back to similac and his poop hasn’t changed til today. His poop for a few days was stringy I’d say (1st pic; my husband said it looked mucusy) but then today his poop changed into 2nd pic and looks a lot thicker but now I think it looks mucusy, compared to the first. I’m not sure what to do. He used to poop every feeding but since yesterday seems like he’s pooping a littttle less now than what he was. Advice or experience on this? I’m afraid he either has an internal infection or can’t take dairy. He’s been formula fed since day 1 also. I’ve been working on pumping to regain my milk supply as well.