Is this a sensory thing?

[Hipposat]

4yo DS (not yet diagnosed but going through the process) has recently started having meltdowns over things that never used to bother him. He’ll have a meltdown if the living room curtains are open and won’t calm down until I shut them. At least once a day he’ll push/drag me towards the living room door and cry until I am out of the room. I go and stand in the kitchen for a couple of minutes, try and come back in and he’ll either cry again or be fine with me coming back in. I am presuming it’s a sensory thing but I’m still learning

It may be a sensory thing.

It could also be overwhelm from other stressors. For example, does this happen more after nursery/school?

As PP has said it may be sensory and the change may be due to other factors. New behaviours can be difficult to unpick.
It has been sunny recently so may be too bright with the curtains open for him? Do you have blinds? You could try a peaked cap or sunglasses for glare.
It could be that he knows once the curtains are closed he doesn’t go out ( so no surprises, Nursery etc)
Some children are fixated on doors open or closed lights on and off etc.

Pushing you out of the room is more of a concern and needs addressing if possible. He needs to know that there is a “ safe space” he can retreat to that you don’t enter if he doesn’t want you to e.g.a pop up tent if you have room ( maybe a bed with under bed space once older)
He does need to learn that shared spaces are just that, shared. Does he only do this to you and can you pinpoint any times or pattern?
As a parent it is awful to see your child distressed and you want to try to make him calm and happy.
I would agree a strategy for this and try your best to stick to it. Use stop or no ( unless this is a trigger word) if he tries to push or pull you. Sit down and say “ Mummy is staying” don’t negotiate or try to reason with him. You might need to use “ planned ignoring” which can be an effective strategy ( as long as he’s safe and not hurting himself)
He needs to learn that he can’t just push or pull adults to get them to do what he wants.
What is his expressive communication like? Is he able to make requests?