Hi S.,
Even that you don't believe to let the bb crying and falling sleep is working. I have 2 son, 2 yrs and 8 mn. With the first one, Jordan I didn't believe it and the peditriacian told me to do it since he was 2 weeks, but of course for as 1 st. mom I tried, It didn't work and I wasn't consistence after that, then about 7 months we start againg and the firsts days he cries a lot and I just check on him every 10 or 15 min. and tell him that I loved him but he has to sleep by himself, the crying was better maybe after 2 weeks, I don't remembered. I did the same with the second one, Joshua and sometimes he still crying even during the day nap, sometimes in the day he falling sleep and cries for 5 min. or sometimes is more but no more than 30 min that I am going checking on him and if he stand up in the crib and can't sleep I take him.
It works to have a routine, like taking a shower and then go to sleep, or read to him, to put music, something that he know is time to sleep.
I have a friend that she has a boy that is 2 1/2 yrs. and they still having problems to sleep by himself or they are putting him to late.
Don't let him take nap in the afternoon too late, depends on what time you put him to sleep is the time that he is going to wake up.
Example, if you put him at 8.00 or 8.30 he probably wakes up at the same time in the moorning.
I hope I can help you and he can do better, hearing the scream is hard and a little painful but is going to be just for a short time.
God Bless you and I pray for both of you that he is going to do better and you too.
A.