I had my first b12 injection 3 days ago and have had dramatic results. My vision has gone from blurred and shadowy to clear and bright, my energy level had dramatically risen to the point I am slightly twitchy as if suddenly having too much thyroxine. My concern is that my blood pressure has gone up to 165 when it's never been above 140 before. Is this a normal reaction. Doctor did not seem too concerned and gave me second injection tonight.