Also, one single person's experiences with the flu vaccine are not much to go on when making conclusions about the effectiveness of the flu vaccine for millions or billions of people.

Just to provide a counterexample, my own experience has been that I used to never get the flu vaccine, and once got so sick with the flu that I thought I was going to die (later I learned that some people actually do die from the flu). Then I started getting the vaccine every year, and since then I mostly didn't get the flu, but in the years I did my symptoms have been relatively mild and short-lived -- it usually lasts a day, and I don't feel like I'm going to die; instead, I just get some weakness and muscle aches.

Another thing to consider is that there may be other reasons for getting sick or not, apart from your vaccination status. I used to have a poor diet and some nutrient deficiencies, but since I improved my diet and started taking supplements like vitamin D and B12, I very rarely get sick. I think my immune system is probably just generally stronger than it used to be.

So to really make solid conclusions about the effectiveness of flu vaccines, you not only have to study large groups of people, but you also have to control for all the other factors that could potentially influence how frequently and how severely people get sick from the flu.

You say you’re not taking an anti-vax stance, but when you discount scientific evidence in favor of your own anecdotes and make up theories about vaccines not containing what they say, that’s exactly what you’re doing.

I got the flu as a teenager one year when I didn't get the vaccine. It was really bad, like 10X worse than a cold. I'd have rather died than kept living like that -- knowing that it would end was actually helpful to my ability to psychologically endure it.

I've gotten the flu vaccine every year thereafter and never got the flu again over the next two decades.