J&J in April. Pfizer booster in December. J&J was a day off work. Pfizer was a punch in the arm at the site of the injection and joint pain in that arm. It seemed to spread with some strange muscle pain. I then got a cold or flu that created thick mucus. Rapid covid test negative.
Since I don’t know “what caused what” I’m not thrilled with the idea of another booster any time soon. It will be well into the year before I consider it.
This seems like a good thread to put this recent study.
This was a meta-review (they didn’t perform any studies, just used data from existing studies) aimed at determining the extent of the “nocebo” effect in vaccine aftereffects. A nocebo effect is the phenomena of people receiving placebo in place of medication reporting side effects for that medication (side effects they’ve been told about).
The authors of this study wanted to determine the extent of the nocebo effect in COVID vaccines.
The bottom line was they did find a fairly significant number of nocebo reports, which brings into question how many nocebo type aftereffects are contained in the reports from the population of actual vaccine recipients.
For those disinclined to read the paper, here’s a bottom line section (AE is Adverse Events, i.e. reported after effects):
In this systematic review and meta-analysis of 12 articles including AE reports for 45 380 trial participants, systemic AEs were experienced by 35% of placebo recipients after the first dose and 32% after the second. Significantly more AEs were reported in the vaccine groups, but AEs in placebo arms (“nocebo responses”) accounted for 76% of systemic AEs after the first COVID-19 vaccine dose and 52% after the second dose.
Noteworthy is the types of nocebo effects most reported were fatigue and headaches.
Not in my case. Got Janssen in July and then Pfizer two weeks ago. Bedridden for two days on both occasions with quite a fever and other “good immune system response” symptoms. Got Covid before that in second wave. Bedridden for six days. One more shot and I’ll be even. 
I’ve had a very noticeable hyperventilating for two or three days after each of five Pfizer covid vaccines, getting the fifth one this afternoon. I’ve never had lung problems, outside this vaccine so discount it each time. Most of my relatives have preexisting conditions that would have made contracting covid a hospital stay. Since I spend so much time with them and also sitting in intimate settings at work, i’ve decided to suck up the vaccine effects.
It’s weird how there’s some part of the Pfizer shot that gives me that same hyperventilating effect, yet haven’t figured out what it is yet.