Do you want to be a single parent or not? How will this affect your life in say ten years? Fifteen ? You will still be supporting this kid in twenty years time, too. I would think of that. Are you one hundred percent you will never become resentful or bitter with this child because you need to sacrifice your lifestyle to take care of them? Your time? Your money? An unplanned pregnancy already is deserving of that question, and with a single parenthood unplanned pregnancy you better be absolutely sure of what you're getting into. It's not the money, it's the dedication.
Are you considering getting into another transactional relationship after this one? A child might make things more complicated too. A lot of men want a lady to keep them company, but not all are happy with a child tagging along.
I'm finding it hard to believe someone would be so ambivalent about completely changing their life like that. You say you would want the best for the child. Can someone have a great life without one of their parents? Sure, but whoever is left taking care of them must be absolutely devoted. You can't backtrack.