Are you supposed to love your child unconditionally from the moment she arrives?
The conventional wisdom will make you feel like that is the only way, but for some parents it might not be the case. For various reasons a child might cause physical and emotional pain, and it takes time to get over it; years for some. The best thing you can do to get through this faster is to talk with your significant other.
What is some valuable insight for first-time parents ?
There is a lot of worry about every single problem. Take the pressure off of yourself and don't worry as much. There is enough stress as is with lack of sleep, disruptions in lifestyle, etc. Just focus on your child, the present moment, and the core responsibilities of helping them thrive.