Anxiety Support Group
Anxiety is a physical condition marked by intense and persistent feelings of distress, fear, angst or dread. General anxiety caused by routine day-to-day stresses usually passes quickly and is experienced by almost everyone at one time or another. However, such feelings that linger over time and are very difficult to cope with, and which lack a clear cause, may indicate...

You are going to be just fine, it's normal to have these fears with your first one. Take care.
Every first time mother can relate to this very well. Our hormones are all over the place for the first few weeks after birth, they can bring the most confident and secure person down into a falling heap! Gotta love those hormones!
Try and get lots of rest, Lack of sleep can make us feel worse.
Babies cry and poop, that is basically all they do for the first few weeks. Crying has NEVER hurt anyone, when he cries it can be because he is overtired, hungry or just plain unsettled. It has nothing to do with you as a mother. You will slowly learn his certain cries and your confidence will grow.
After 4 kids I can honestly tell you that the first few weeks of parenthood is one filled with mixed emotions. Hang in there. Take deep breaths, lots of photos and try and enjoy each moment as much as you can, they do not stay little for long!