Orange yellow mucus poop? No pics but need help lol

I started his Zantac up again last week and his poops have changed. I was worried about infection but he's fine otherwise. He is drooly but hes only 3 months so idk if he could be teething already. I wanna call the dr but I feel like they will just tell me to keep an eye on it lol did anyone notice this when they did zantac for their baby? Hes already on a no dairy formula so its not dairy. Thanks!! His poops were like a greenish and soft, now they're running and mucousy and yellowish orange :(