The exposure you've described doesn't suggest significant toxic dosage; nowhere close, actually. Your baby's perfectly fine.
Taken from americanpregnancy.org
'Paint And Pregnancy: What If I Have Been Exposed To Paint Already?
Currently, there are no studies that document harm to the baby during normal and incidental exposure to paint (i.e. painting a room). The only studies that note a potential for miscarriage and malformations has to do with the higher levels of exposure through recreational use (sniffing and inhaling regularly).
If you have been exposed to paint, rest assured that the likelihood of any problems is low. According to the FDA, today’s paints do not contain lead and are probably not dangerous. Let your health care provider know of any paint exposure and together you can discuss the potential risk.'