Macrocytic blood picture Second opinion.

Hi Doctor, I am having variations in RBC from past 3 to 4 years and it varies from 3.3 to 3.9 (4.5 -6.5 normal)  and Hb is always 14-16 and always in limit. History- Had chicken pox in 2016 and some Cervical lymph nodes came and FNAC - Reactive nodes Usg & Mri showed normal and been to oncologists and they told me the 3 to 4 nodes are not significant. Have also done smear & LDH and  were normal. had a blood in urine in 2019 Nov and usg ,xray & kidney related blood tests were normal.They found citrobacter ferundi bacteria was causing me the issues and after medications everything got recovered .Google-Citrobacter occurs in people those who are having cancer and I asked my nephrologist and he assured me there is nothing like that. Now again did a blood test Hb is 13.6 & RBC - 3.35 and saw Physician and he told me to B12 results was 56 which is less and serum Feratin is fine. He suggested injection for a week + folic tablet 30 days.impure veg.Is there anything to worry looking my history?