Hay, I totally get your worry, lalo na ngayon na pregnant ka pa, hormones are real, alam mo! Since the doctor already checked and his breathing is okay, it's likely the allergy talking, pero kung parang hindi tumigil within the full 5 days, don't hesitate to follow up ulit kasi sometimes dry cough from allergies takes a bit longer to settle, especially pag newly identified pa lang ang trigger. A few of us mums had similar situations with our kids and we found na consistent avoidance talaga ng trigger foods plus patience helped more than we expected, pero if it gets worse or you notice anything else off, definitely call the doctor again para ma-ease your mind. Breathe, mama, your protective instinct is normal especially while pregnant, pero sounds like you're doing everything right.