B-12 deficiency symptoms per web-MD:
Weakness, tiredness, or light-headedness
Rapid heartbeat and breathing
Pale skin
Sore tongue
Easy bruising or bleeding, including bleeding gums
Stomach upset and weight loss
Diarrhea or constipation
I have none of these symptoms, so must be getting enough B-12 from my diet.
A b12 deficiency that is advanced will mimick ms