The biggest side effect will be that your odds of dying or have life-long disability's due to a covid infection will drop significantly...
Sure, there's a chance you'll develop a blood cloth, but the odds of dying or thrombosis due to covid is much higher (even in healthy humans).
It's like putting somebody in front of a table with 2 revolvers on it: one contains 1 bullet out of 6 chambers, the other contains 5 bullets: if you're forced to play russian roulette, which one will you pick?
Same with covid: it's going to be around for a while, odds are pretty big you'll get infected sooner or later... You have 2 choices: develop immunity by actually going trough the dissease, which still has a 0.2% mortality rate for my age group (according to
https://www.statista.com/statistics/1106372/coronavirus-death-rate-by-age-group-italy/), and we're not talking about the morbidity rate.... Or the second choice is getting a covid shot, which has a 0.0005 chance of getting a blood cloth (
https://www.the-scientist.com/news-opinion/blood-clot-risk-from-covid-19-higher-than-after-vaccines-study-68675).
Basically, my odds of dying from covid are 400 times higher than my odds of developing a blood cloth (and there's about a 50/50 chance of dying from a blood cloth). So my actual odds of dying of covid are about 800 times higher than my odds of dying of the vaccin. I like those odds.
But kidding aside... My wife got vaccinated about a week ago... She had some flu like symptoms for about a day, and her arm was sore for about 2 days... She's working as a teacher for disabled children, so she got priority for her vaccination. I kind of envy her, if i had the chance of getting vaccinated, i'd take it right away.
My grandmother got both polio and whooping cough when she was a kid. She told horror stories... My daugher no longer has to fear of getting paralysed or even dying BECAUSE my country actively vaccinated for a couple generations already. If they didn't these diseases would still exist. I'm not saying that there can be no side effects, i'm just saying you have to look at the big picture: how many people will die because of the vaccin vs how many people will live because of the vaccin.