I give several B12 injections a day as a community nurse and it is rare to have a bad reaction however this sounds definitely like an adverse reaction and if someone reported this I would not give any more until it had been checked by the GP. There is a yellow card warning system for medications and this would need reported on that. Occasionally it can be the batch that is the problem.
Relationship Investigations in the Digital Age: Contact Wizard Web Recovery
Cheating Spouse Concerns and Digital Evidence: Contact Wizard Web Recovery


