I'm glad that things are going better hun

Sometimes mums with babies who don't like lying on one side find that osteo or physio can help a lot, especially if the problem has been there since birth. I can understand you being concerned though, and it might just be something to keep in the back of your mind if this doesn't settle down in a couple of days. If you do go down that path, there are some osteos and physios who specialise in babies.

Given that this is more recent, another possibility is that he has an ear infection on one side. Sometimes this makes them uncomfortable on one side and could possibly also explain the unsettled behaviour.

In the meantime, if you are not sure whether or not he is getting enough milk, the nappies will be able to help you out. 5 or more heavily wet disposables (or 6 - 8 pale wet cloth nappies) in 24 hours means he's getting enough.

To answer your other question, many babies feed from one side only and there is no problem with this - the mum might be a bit lopsided but she's probably the only one who will notice! However, because you have been feeding on that side, mastitis is a risk when he's not feeding from it. Expressing regularly will help with that and also checking it regularly for lumps.

I hope things continue to improve hun