Vitamin d deficiency. On this. thnx!

My vitamin d reports have come and it's 5.5 n vitamin b 12 is 166 which is deficient and seems to be pretty low. The doctor has recommended me some 8 injections( please see attched pic of prescription) for both vit d n b 12 n some vitamin d supplement which is tab bicidak 60k - once a week for 8 weeks. However when I showed the reports to other ortho he advised only 1 injection I.e. Inj. Arachidol 6L I.U n tab Bio-D3 strong (2 tablets daily for 1 month)...now I am pretty confused whether I will wid 1st doctor who has recommended total 8 injections n other medicine....Can someone please give a Frank n unbiased advice on this...becz in today's age it's become very tough to trust a doctor becz it has become a business n not a noble profession which it used to be earlier....I appreciate a unbiased advised on this...thnx