I agree with many other posters, either allergies or toxins. If you pre-washed the bedding, it is probably the new bed. I would call poison control and I would also find out where the bed was made. We all know about all the problems with toys, paint etc. For now I would definately put him back in the crib and get the bed out of his room until you know for sure what is causing his problem. John Travolta's son Jett got sick from carpet cleaning solutions as a toddler and came down with something called kawasaki disease and they believe that is what caused his seizures.
Also people in New Hampshire may remember several years ago, a family moved into a brand new house and their new carpeting made the entire family sick. And Oprah had a lady on her show about the same time who was so sick sleeping in her home, she slept in her car until Hazmat came and took her comforter away, which had been cleaned at a cleaners.
So I would say for now, get the bed out of his room and put him back in the crib for now until you know for sure it is NOT the bed. We want to keep him safe.
M. Peploe
livetotalwellness.com