I accidentally drank spoiled milk at 31 weeks pregnant, will my baby be ok? what will happen..it was a big glass

Baby will be fine: You might get stomach ache and vomit but your baby will be fine.

Should be ok: You may get sick with some nausea, vomiting, diarrhea, but it should not harm your baby. Or it may not affect you at all. If you were not aware it was outdated and able to drink it then probably not spoiled or contaminated with the harmful bacteria we worry about. If it was, would expect onset of symptoms within hours of drinking it. If a day or more has passed, you should be fine. Good luck

Odds are: You'll likely be fine. Though watch for either lower(diarrhea) abdominal or upper(nausea with possible) gastrointestinal symptoms. They may never come but if they do and they are severe(preventing you from eating food and staying hydrated or debilitating pain) or with persistent fevers, then you should contact your OB or primary care for further instructions. Keep living healthy.