The sudden depletion of vitamin B12 may also be the cause of the fatigue, dizziness, and brain fog you experience the morning after drinking
Always check that your improvement is linked by taking it out again and seeing if you worsen again

Fatigue accompanied by other concerning symptoms including: Persistent dizziness, lightheadedness, or fainting Rapid or irregular heartbeat Shortness of breath or chest pain Severe or unrelenting nausea and vomiting Inability to keep down food or fluids for more than 24 hours Dark urine, markedly reduced urination, or swelling (signs of dehydration or kidney problems) Yellowing of skin or eyes Severe abdominal pain Mood changes, depression, or difficulty concentrating Signs of potential complications require immediate attention: Stop the medication and seek urgent medical care if you experience severe abdominal pain (especially radiating to the back) which could suggest pancreatitis Stop the medication and seek urgent care if you develop symptoms of severe allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing) Symptoms suggesting gallbladder disease (right upper abdominal pain, especially after eating) Hypoglycemia in patients taking diabetes medications (shakiness, sweating, confusion) Inability to meet nutritional needs despite best efforts, or unintentional weight loss exceeding recommended rates (generally more than 1-2 pounds per week after the initial period)

Alcohol plus an empty stomach plus a fresh shot is a recipe for an awful night
HYDROXO-B12 Injection HYDROXO-B12 Injection is used for the prophylaxis and treatment of pernicious (Addisonian) anemia and other macrocytic anemias associated with vitamin B12 deficiency