I just had a little tiredness a day or 2 after, and a bit of nausea at times- but not any more than a couple Tums, rest, or electrolytes wouldn't take care of. Protein, electrolytes and fresh air outside a bit may help. Give yourself grace and take it easy if you need for a day or so. Silly but, I cough when I put the needle in and I do not feel it. The shots have been life-changing for me! Best of luck.