Father of 3 here; 1 year, 4 years and a 7 year old. I was also nervous about first kid, I only have few things. Every kid is different, but there are always some generic things to say.
Relax, kids mirror your emotions and can feel if you stress. Even if you are up mid night and are stress about sleep. Just take it easy. Kids don't do it to be mean. They don't have those kind of thoughts.
Kids are simple. They want affection, food and sleep. But they can't get any of it on their own. To begin with, they barely even know if they have feet and hands. So it's your job to help em out.
Babies can be crying or complaining for many reasons; Maybe something is itchy, they are hungry or need to poop. So relax, it's not always something bad. Give them some love, check their diaper, keep tabs on the time since last feed.
First time is always bad. First couple of weeks is just stress. You need to get into a new rytm, but it gets much much better after 2-3 months, where their stomach settles in, they settle in and you can start to enjoy it much more.