Always good to have a reason I have also had this happen when my folate was low , it may be worth you getting it checked I had self inject my B12 every 4 weeks for the last 20+ (cannot really remember how long accurately), and 2 months ago got a similar 'electric shock tingling' all over my body - head, face, arms, hands, legs, feet etc within a couple of minutes of injecting, which lasted about 3 seconds or so
Sep 18 2021;13(9)doi:10.3390/nu13093256
* -Pure Powder * -Transports Fatty Acids* -Boosts Cellular Energy* Recommendation: Now Foods suggests taking 1/2 level teaspoon, 1 to 2 times daily as needed
N., Wu H
L-Carnitine helps the body use fat as a source of energy, making it an excellent supplement for individuals who want to improve endurance, support weight management, and maintain energy throughout the day