It may be that you are naturally immune to it. Many people who were exposed to previous virusus are immune to COVID-19, and many people have developed immunity to COVID-19 because they were unknowingly exposed and developed immunity without ever knowing it. There are journal articles from epidiemiologists who estimate the number of people with immunity now is pretty high.

Having said all that, I did see somewhere that despite the initial blood clot issue, there are fewer adverse reactions overall to J&J.

But in making your decision you might also want to think about which vaccine is the most likely to demand a booster shot. I read recenty that Moderna is claiming that with their shot there is no need for a booster yet. Though I think it is a slippery slope - now the powers that be are demanding vaccines, later they will demand booster shots. That's why I'm waiting for the Complete Vaccine.