HI Sav. Taylor started teh short naps OVERNIGHT at 7 weeks and they didn't start to lengthen again until she was about 14 weeks. At this age, it is very common for them to start taking short naps as they are organizing their night time sleep and then will start to organize day time sleep during the 3rd and 4th months. So I would probably guess that your ds is not a short napper by nature (only about 5% of all babies are truly short nappers), but just going through this developmental change in his body clock.
Every day I worked on extending her naps because she was NOT happy on just 45 minute naps and it was very stressful. So if you want to try and extend them, we can help you give it a go. If not and ds is pretty easy going with the short naps, then don't worry about it. It is your call.
Taylor's naps started lengthening when we moved her to a 4 hour easy routine at 4 months and she finally learned to fall asleep independently.