Watery poop 4 months old

My baby has been having watery poop since he turned 2 months until now 4 months. He’s on full FM, did not change his FM since birth. Atleast once a day or max 3 times a day, only poops after feeding or an hour after or so. Sometimes his poop is creamy but most of the times are watery. Yellow or dark yellow. Is it considered diarrhoea?