Another suggestion...
Hi Susan,
I know everyone here is saying, hold him - it goes by so fast. And I do agree that it goes by super fast. BUT, I have a 3 1/2 year old and 18 month old twins. So, the deal with twins is, you can't hold both of them all the time. (I applaud anyone who can for more than 10 - 15 minutes, it's hard!)
Here is what I had to do with my daughter (3 1/2 yr old) when she was about 2 months. She got so accustomed to me holding her that she wouldn't let me put her down. I used a technique (that sounds so cold, but it isn't) I read in The Baby Whisperer. Basically, it's called pick up/put down. When you put down your little angel boy, and he cries, pick him right back up. Sooth him until he's calm and then immediately put him back down. If he cries, pick him right back up. Sooth him until he's calm and immediately put him back down. You get the idea. It might take about 10 or 15 minutes, but he will realize that you are there to see to his needs and he really can be on his own. You're building his trust in you and his independence at the same time.
I also believe there's no such thing as spoiling an infant - but sometimes it's nice to watch them play in the playpen happily while you do whatever you needed to do. And there's nothing to say that once you've completed your task, you can't pick him up, smother him with kisses and say how proud you are of him!!
My twins learned early on that they sometimes had to wait, and they adapted very quickly and well. (As did my older daughter, BTW.) My favorite memories of the first 6 months with the babies was of my daughter telling my son (while I nursed my daughter), "It's ok, I'm right here. Mommy is right here, too. You don't have to cry - we love you!" That's a direct quote from a then 2 year old.
Hope that helps in the times that he doesn't want to go in the swing.
Good luck and congratulations on your beautiful baby boy!
Tricia