And have you considered why?
I have had around 4 or 5 fillings in my life. Rejected analgesics. Weirdly, it may have been a subconscious knowledge that local anaesthetic didn't work on me (found out via other minor ops, and subsequent diagnosis of Ehlers-Danlos syndrome)
I gave birth to my daughter which was very quick and very painful. None of the pushing that you see on TV births. Literally couldn't speak. No screaming at my partner. I just had to focus and breathe. Also, I was adamant I'd have a water birth and I did. I appreciate this may have been partly due to luck. But I needed that space between me and medical professionals. Didn't want to be touched, so it gave me control.
Are we used to pain in the sense that we are used to masking? It's a possibility surely? We experience things every day that others may not have to deal with. We often deal with noise presenting as an almost physical pain. Along with other sensory issues.
And lastly, perhaps we experience other, physical conditions that we have dealt with for so long before seeking help. In my own case, I've had nerve pain for around two decades. Didn't cross my mind to look into it because I'm just so used to battling and masking so many things.