No reaction - other than slightly sore arm - to first two shots. Got a booster on Tuesday, felt awful on Wednesday (tired and headache), and somewhat better on Thursday (tired only.) I like to think that's because I am having such a strong immune system response.
That's what I'm telling myself too!
I, too, only had a reaction after the booster -- achy, tired (sooo tired). But it didn't last long.
I was exhausted, cold and a bit achy-jointed starting at noon the day after my shot. I went to bed shortly after dinner and woke up at 5:30 am feeling normal. I'll take it!