Spoiled breast milk

After talking to my husband tonight I realized that I gave my 1 month old expressed breast milk this morning that had been sitting out for 24hrs and not the fresh bottle he had made for her. She’d been spitting up much more then normal this am but seems totally fine otherwise. Is this anything to worry about or is she okay if everything else seems fine and it’s been all day since the bad milk? Anyone else given their LO spoiled breast milk and had a reaction? FTM and very worried!