Our DS of 20 months has always been a fab sleeper, like incredibly so, from 3 mo slept 12 hours at night and now does that with one 3 hour nap in the day from 12.30 - 3.30.
I used to be able to put him down in the evening absolutely fine, we have no real routine just book, sleeping bag and song then bed. He would then be put in his cot and say goodnight and put himself to sleep within a few minutes with no crying sometimes just happy chatting, mostly silence.
Nothing has changed in our house, and his daytime nap is still fine, but the past 3 nights he has SCREAMED and banged his head on his cot, it's flipping awful and I just don't know what to do. The first night I left him to cry for a bit but he was banging hard and so we would go in and resettle him which took absolutely ages (hours) before he settled. He is getting so worked up it's very heartbreaking. Then last night was the worst, he ended up in our bed until midnight but not actually sleeping just talking and wanting to play.
The only thing I can think of is maybe somehow related to his speech development? The past few days he has learnt tons of words.. please tell me this has happened to someone else and you've got through it?