Hello, could you tell me if my baby has had loose stools for two days …

Hello, could you tell me if my baby has had loose stools for two days now, yellow in color with fibers? My masseuse said it might be on teeth. There is no fever, no colic, no runny nose. The baby is almost 7 months old and hasn't got any teeth yet. Is this really possible on teeth? Or should I worry and go to the doctor immediately, just in case something infectious?