B12

 Hey everyone,so for the past few weeks and more i have been extreamly tired and exhausted and lot really loosing even though my meals are only a coyple of bites,as well as every once in a while i have pains after i eat on my right side,so we started with doing blood tests,and doc called and told me to come in on thursday that something was not right,i called martine,and i asked her she told me my B12 was extreamly low as well as another level but would nit say which cuz doc might not say anything about thst,but he was calling me for that,she also said this us the reason im so exhaudted its B12 deficiency,and it causes my metabolism to practicly stop so she said with hopefully injections i shouldvbe much better after a few times,,has anyone had b12 deficiency after weight loss surgery?