Tiny black spots in 6 mnth old stools. Formula fed and had oatmeal n bananas in past 24 hrs, help!?

my 6 month old had black specks in his stool this morning, and a couple of red ones. he is on solids and formula and did eat bananas and oatmeal in the past 24 hours. he is playing and laughing and smiling, has had 3 bottles this morning and no solids and isnt being fussy or lethargic. color is normal for formula fed baby.. need help! should i take him to the er his dr office is closed :( thanks in advance!!