Welcome to HCM
It will take some time for vitamin tablet to make your blood level to normal. The cause of the pain should be found out. I think improper placing of the hand by you might be responsible for it.
I advice you to discuss with physiotherapist regarding correct posture while working. I also advice you to go for x ray
shoulder, elbow and wrist to rule out any deformity
Hope i have helped and you got some useful information.
Wish you good health.