Oh my, Please don't let your poor son scream for an hour hysterically! If it hurts your heart to listen to think about what it is doing to him to be in that room, with the door shut, he can't get it open, he's scared, hysterical, screaming for you - and you don't come.
What people don't realize when they try the cry it out approach is that they are in fact harming their children and themselves. You aren't listening to your gut which says go take care of the baby/toddler, and the child who is freaking out, scared silly and desperately needing his parent to come rescue him not to mention his blood pressure is sky high from the hysteria. If you continue each night to let him cry it out like this, he will eventually stop. But the reason they stop crying is because they have given up believing that the parent will come rescue them. How sad is that? And, worst of all, their ability to trust that their needs will be met is damaged.
I liked the one gal who soothes her child to sleep. That is wonderful, the child knows he is safe and loved. You cal also seriously establish a bedtime routine to work with that, bath, stories, and bed...something along those lines, so he knows that it is time to go to sleep. Eliminate anything that is stimulating about an hour before bedtime to he has a chance to wind down. Take him to the park or outside just before getting ready for bed to run off some extra energy.
Above all, do NOT let your baby cry like that. It isn't doing any of you any favors. It doesn't feel good for either of you so why continue? Bedtimes should be relaxed and enjoyable - as much as possible. Sometimes you are going to have a rough night - but that is life. But, listen to your gut - do what feels best for you - that which does not break your heart or your child's...
Good luck...
warmly,
J.