B12 deficiency: Symptoms include feeling tired after a good night's sleep Express.co.uk Association of Vitamin B12 Levels with Sleep Quality, Insomnia, and Sleepiness in Adult Primary Healthcare Users in Greece Constant tiredness even after proper rest? Feeling dizzy, weak, or noticing tingling in your hands and feet? These are not normal everyday symptoms they could be early warning signs of Vitamin Understanding the B12 Vitamin Shot: Benefits, Risks, and Dosage Guide