I Have Been Diagnosed With Vitamin B12 Deficiency (166 ).

I have been diagnosed with vitamin b12 deficiency (166 ). I have been prescribed VItcofol injection alternate days. But as I started taking the injections, I felt heaviness in my head, weakness in my left leg and knees.
I got back to my doctor on this symtoms. He said these are normal symptoms for b12 deficiency. He has now prescribed me Ciplar 10 and ELiwel 5 mg. When I read about these drugs online, the results terrify me saying that one for migraine and the other is for lowering blood pressure. I am doubtful whether I should go back to my doctor and ask why he prescribed me these tablets.