It shouldn't worried you if your baby cry because you should be prepared before hand. Every baby is different and some might cry less and other might cry loud and hard for no reason. Initially you will have to learn the signs if he is crying because of hunger, sleep or want environment change like if he is too cold or too hot. Mostly babies are little quite in early days and then he can start crying more often, even some times for no reason. You can check, if he needs diaper change, try to change the environment, if he wants to sleep, or he might not be liking crowd.
If you think that the tiny baby have tiny stomach and you wont have to worry about feeding him often then you are wrong. They need constant feeding, though small amounts every 2 hours or less then that. If you are giving him formula then 1 to 3 ounce is needed for every feed. However with breast feeding, you will get idea about how much baby needs each time. You might need a day or two to understand baby's signs when he is hungry like crying style or turning his head to feed. It is important keep check on the weight of baby. If he is not feeding enough and loosing weight, then you should make effort to feed him or else check with your pediatrician. Though in initial days, baby will loose some of his weight but will start gaining in again and should have same birth weight at two weeks.
Also keep check on the burps which are important for babies. After each feed, try to burp him by holding to your shoulder, keeping his head resting on it and gently patting on his back. Some babies do burp quickly and some might give you hard time which was the issue with our baby. We tried all methods to burp him and he was rarely giving us fruit of our efforts. Sooner i realized that he have hiccups more often and learned that this was his way of telling that food is going down. Don't be alarmed if your baby have more hiccups then burps and be ready for some spit ups as well which can be often, though i was lucky to not have them.
Pee and Poop
During the first day or two, baby's pop will be dark having sticky texture which is called meconium. After that it will be more like yellow to brown or little greenish. If you observe a red flecks or white colored poop, then consult with doctor. They can have 5 wet diapers in a day or more according to doctors but it is not necessary. You can get fewer on some days as well. Also it is considered that formula fed babies poop less then breast fed babies as formula takes time to digest. However if he skips a day or even 4 days. You need to check if he is feeding fine and have no issues then it is OK or else get advice from doctor. Your baby might have gas issues or very rare chance of constipation as breast fed baby have very thin poop and you might think it is diarrhea but if he is not fussy and feeding fine then you don't have to worry as it is normal. Overall you might get confuse initially but if your baby follows a pattern then it is normal, although sudden changes need to be checked.
New born babies will sleep almost 16 to 18 hours each day, though not at once but in short naps and then after feeding they may be asleep again. You can track down the timings and when it is time for his sleeping, provide the comfortable environment like swaddling and rocking to sleep. Babies do like snug or confined environment to sleep like they were in the womb. If you keep him swaddled from start when he needs to sleep, it can bring a lot of ease in your life. Whenever you will swaddle him, he will be ready and quickly feel asleep. Also with swaddling, there are less chance of him jerking awake or being afraid of his own limbs movements.
Don't leave him alone on couch or bed for safety reasons and keep his crib clean from loose blankets from him so he can breath properly. The best place for babies to sleep is cloth swing aka hammock. It no doubt have made life easier which you can keep on stand or tie at any better place. It not only keep the baby safe from jerking awake but also provide snug environment.
The things i mentioned are just to get the idea of getting started with your new born. There are no hard and fast rules and as you spend days with your baby, you will notice what is best for him and how to deal with his crying or uncomfortablity. I have shared few of my experiences and you are going to have your own. Let me know in comments what things you have learned or if there are any tips which you tried and that worked.