I would feel nothing. I would not exist. It's a pretty simple answer to a pretty dumb question pro-lifers like to ask to trip up pro-choice advocates.
To not exist is neither good nor bad. It just is the case (in a negating sort of way). So if I never existed, it would never have mattered—to anyone. Of course, existing now matters to me and others who love me, but if I never was, I’d never care and neither would anyone else. There would be no me. And that would have been fine.
But to use the kind of argument as the questions above give is to commit a gross error. It demeans women who have become pregnant by telling them they have no free will over their bodies. In the (usually) well-intentioned efforts of pro-life advocates to esteem the personhood of the unborn, they take away the personhood of the already born. This is a case of mixed-up priorities. To be pro-choice means that one fully respects the personhood of the woman just as I would want everyone to respect my own personhood.
I can say what I say because I exist. But if I didn’t exist, so be it. There would be no skin off my back (literally and figuratively). Pro-lifers need a new argument.