Why do new parents feel pressure what are some of the biggest sources of worry for new parents?

Well its because they feel rushed and have never experienced or don't know what to do ...

New parents get really pressured, some reasons being that they need to find an occupation that will provide for the whole family's needs. They also worry about the child getting sick and the costs that they'll need to pay for the kid. They will also want the best life for their child (hopefully) therefore letting them have rhe responsibility of making that possible. They are taking care of a human life, a life that they created.