Night 1 of getting albie into his own room after a year!! He's been in our bed since he was about 4/5 months old he…

Night 1 of getting albie into his own room after a year!! He's been in our bed since he was about 4/5 months old he slept in his own crib up until then but we enjoyed having him in with us, we've tried every now and then since but something's always happened with him being unwell so we stopped trying but now he's a year old it's time however since we last tried his temper and crying has got so much worse! I don't know when enough is enough and the crying becomes to much do I let him just cry for hours and hours? He's got his milk in with him cos I didn't want him to fall asleep with us then put him in his bed and wake up hours later and be confused where he is I feel like whatever I'm doing is wrong