Oh Adria... I hear you in so many ways. I truly think as someone just said, that we are all at that stage.... but I think each in different ways.
You have my thoughts.. Big hugs.
I will share what I do with Owen and seems to work most times for us. I let him fuss.... not cry, but fuss. If it becomes crying I go straight in, but sometimes he fusses for 15 minutes or more. I figure, as long as he's not crying, then he's not in any pain and maybe he's just grumbling about a bad day or something. (I alwasy try to give him an old man's voice like I read in BW... it makes it easier for me.) Also, you let him sleep in his swing.. we used to do that too, but now Owen sleeps only in his crib. We leave a little music on to block out the outside noise. Maybe your lo has out grown the swing and is ready to sleep laying while being still.
One other thing I noticed is that you hold him for20 minutes wtih the paci. My wind down with Owen is not nearly that long, but I'm not sure waht the "norm" is. When he begins to look tired, I take him to his room, pull down the blinds, turn on his sheep that makes white noise, I swaddle him, sing a lullaby and then say have a nice sleep. I doubt it takes longer than 10 minutes max. But my lo is an Angel baby, so I haven't struggled too much with naps. Hope some of this may help you.
Lastly, I would like to say that I would love 4 hours of continuous sleep! I cannot believe that I once thought I knew what it was to be sleep deprived.... On occassion it has been 4 even close to 5 hours. But not often enough. I can't wait.
But then again, me and DP are already talking about starting on #2. I figure I want to keep it close together and never be this sleep deprived ever again.... LOL
Keep Smiling! (i know i try)