(((Hugs))). It can be so tough at this young age. It's ok to use whatever works to get them to sleep at this age, because as you said it can be hard to get them to feed and to sleep more when they're so OT.
I agree that a swing is a lifesaver. Also, do you have any baby carriers? My son loved to sleep in the wrap when he was tiny. I would wear him and bounce on an exercise ball and that basically always worked! Also, some babies love being pushed in the stroller.
Let us know how you get on.