loliac-
First of all, congrats to you on your new LO! I am not an expert, but I believe that at Josh's age it is completely normal not to have regular naps. My LO is 5.5 months now, but I felt like the first 6 weeks were complete chaos! We just followed LOs cues and tried to encourage sleep, but I think at that young of an age they don't tend to sleep for very long at one time. My advice is to let him sleep where ever he will right now. I don't think that LOs get into bad habits that young. I remember feeling like LO was never going to sleep and then suddenly he started falling into more of a routine, but for us it wasn't until about 2.5 months. Before that we just followed his cues and let him sleep when he needed to. I hope that I am not steering you wrong, but just remember each stage only lasts so long. It will be over before you know it. For now, just follow him! He will tell you when he needs to sleep, eat etc.
best of luck! Erica~~