M.K.
Congrats on your baby boy! I agree with the other Moms...a baby of his age should not be sleep trained. When he cries, he is definitely communicating a need -- and it may simply be for physical contact. Babies require this as much as they need to be fed or a diaper change. At this age, it is not an indulgence. You are actually fulfilling a very important physiological need.
As for the "confusion" over day and night, I remember my Pediatrician telling me to limit the duration of daytime naps to no more than 3 hours. I tried it with my first born but it didn't seem to make much difference. This is something the babies grow out of over the first couple months.
During these first three months of getting to know your newborn, this is a great time to start watching for his sleep cues to emerge (he may tug at his ears, etc.) and discovering which soothing methods he starts to prefer (does he like when you sing, etc.)
It's also the best time to find a sleep training method right for you. I recommend "Healthy Sleep Habits, Happy Baby," by Marc Weissbluth, MD. It is written in sections, according to month of your babies age (all the way through adolescence), so you only have to read the introduction and then the section on your baby's age.
I wish you and your baby all the best!