2.5 year old massive regression in sleep

[tinypop4]

My DS is 2.5. He's been a good sleeper since 8 months when he started going through save the odd early morning.
Last 4 nights have been a nightmare- he wakes up about 10 and till 2-3am screaming for cuddles, then he gets one and as soon as I put him back he starts screaming again and getting out. Does the same for DH. Gets increasingly hysterical and won't stay in his room. Screams a variety of things about wanting us to sleep next to him, cuddle him which we do but none of it keeps him asleep.
It's just going on and come from nowhere, no idea how to deal with it.
If he comes in our bed he just wriggles and sleeps lightly not falling into a proper sleep and waking up whining every half an hour.
He has no temp and calpol isn't helping

My dd just turned 2 has just started doing this exactly! Knackered after a night of wriggling/fitful sleep in our bed after she woke up screaming about 3am. Took 2.5 hrs to get her down in the first place and she never used to be like this!
Got no advice just a lot of sympathy. I put it down to me increasing my hours a bit at work. Maybe it’s just a clingy phase?
I was more firm tonight though as just can’t keep going, so tired. Now she is asleep, hopefully for the whole night (please please!!)

Yes Dafodil I've also been working extra as Christmas is my busy period. I'm hoping it's just a short phase of mild insecurity - I have 3 weeks off as of Monday so I hope a bit of time with his will help.
I've just managed to re-settle him in his own bed but expect he'll wake again soon

It’s not his back molars coming through is it?

How was your night Tinypop?
Dd woke up twice but thankfully settled a bit better!

He has his molars baba.
Daffodil he woke up about 9.45 and I managed to get him back to sleep by 11.30, he then slept rest of the night. This is better than previous although not great

Onwards and upwards!!

Second set of molars would be my initial guess.

Next I'd consider illness, especially seasonal invisible illnesses like sore throat or general aches and pains of a cold.

If it's not pain, maybe look at her overall sleep (inc daytime) and consider if she is over tired or under tired.

Next consider that natural brain development will mean toddlers imaginations start to make then scared of the dark, frightened of monsters etc. Maybe try leaving the door open it light on?

Thank you Faye. I'm pretty confident he isn't ill but I hadn't thought of him being frightened of the dark or nightmares. I'll have a go at a nightlight or leaving the door