hi, i have a 1.5 month old son. he was first on hypoallergenic formula but stool was hard, so doctor changed to soy-based. after 2 weeks, we noticed some threadlike blood (very minimal-one or 2 small only) happened thrice, and oily stools. Doc changed back to cow's milk hypoallergenic but different brand (similac hw). Now 2 days, no more traces of blood but still oily and watery? is there anything wrong?