Infant won't let me put him down in the daytime?

My son is 8 wks old. He sleeps fairly well at night (4-6hrs) and takes a morning nap (30-45min) and an early evening nap (1-2hrs long). However, during the day, I cannot put him down. He doesn't like a sling, a carrier, a carseat, a swing or a bouncy chair. He cries after only a few minutes in each (of course, I have to have him in a carseat in the car- he cries until he finally falls asleep). He doesn't "do" pacifiers either. Any other suggestions from others? Strollers only remotely successful during walks - he usually cries until he falls asleep in strollers. Swadling doesn't work either. He really is a happy baby as long as someone is holding him. My pediatrician recommends letting him cry, but I'm not really comfortable with that. Thanks