sleep

so for ages me and my son coslept and he wouldn’t sleep in his cot due to having to share a room we have moved house now and he has his own room for ages we was doing really well he slept in his own cot in his own room for ages from 7/7:30 till 6/7/8 am but lately he’s been waking up at 4:30/5 am i’m not sure if there’s a sleep regression or his teeth are bothering because he’s also been waking up at 12-1 am i don’t know what to do or why this is happening any advice please x tyia