You have been misled. The subjective perception of pain requires communication by the perceiver. Even adults able to communicate their perceptions do not necessarily show a correlation between physical movements in response to pain and their own subjective rating. In short, whoever told you they could make such a comparison was deceiving you.
Even more important, however, is the *suffering* associated with painful stimuli. All vertebrates respond to pain. Are you suggesting that inducing pain in all vertebrates be made illegal, or that it should be legal to kill fetuses provided it causes no pain?
The problem with this argument is that it sadly ignores those qualities that make humans unique from other creatures. You stipulate a higher appreciation for humans, but only in the context of their similarities with other animals. But it is those uniquely human qualities that makes human suffering exceed that of other animals.
Are you fine with the fact that since 1973, 42 million reported surgical abortions have occured in the US alone (1 BILLION plus globally since 1973)
No. But it is a travesty to diminish the suffering of the holocaust by equating them.