Am I expecting too much from DS

[Appletree213]

I think this is my 3rd time of writing so I'll try to keep it brief.
DS is two and half years old.
We are really struggling with toilet training. We had pretty much mastered it for a few weeks and it all went downhill when nursery tried implementing from their side. DS becomes very upset and stressed when nursery take him to the toilet and I've suggested various ways on how to comfort/help/not help DS - DS is extremely independent and often trying to help him causes a meltdown, but none of my suggestions have worked which makes it challenging to continue toilet training at home. I've tried sticker charts, books, endless amounts of praise and explaining it but to no avail.
There's no rush for toilet training as he's ready when he's ready, but I can't fathom as to why he was doing so great with toilet training to well nothing which moves me on to my next point.
We moved DS back to nappies as I'm not confident he's ready. DS will now never tell us if he's done a poo in his nappy, when asked he will say no. (DS is quite clever and understands and can communicate with us very well.) Today, I woke him up from his slumber, and he must of messed with his nappy in the night resulting in him being soaked through which I felt awful about. Despite being soaked through, he put up a huge fight to have his nappy changed - he's not sore anywhere as that was my first thought. He's always told us before if he's done a wee/poo so I can't understand what's changed?
We have a very strict morning routine unless it causes a huge meltdown, things you/I wouldn't even bat an eye over, so how, when it comes, can I introduce going to the toilet in the morning without it causing huge stress for him?
I may be expecting too much, I think from my POV I can't understand as to why he's regressed in certain areas when we pretty much had them nailed. (Role play is another, he used to love role play but now for instance if I say let's pretend to eat, he will physically try to eat it - could be an envelope, play doh...)
I did say I was going to keep this brief so thanks if you've got this far, just trying to paint the whole picture to get some advice.

I idea why he's regressed but I think you've done the right thing in putting him back in nappies.

Have the Nursery raised any concerns about his behaviour? Do they think the resistance and rigidity are usual?

Thanks @PritiPatelsMaker for responding!
They did raise concerns recently that DS seems to be changing in the sense he isn't socialising as much at nursery and instead sitting alone looking frantically around the room. They think he may be quite overwhelmed which coincides with him constantly chewing whatever he can find.
He also seems to go in these trances, where you can't talk to him even though you're standing in front of him. I genuinely don't think he's ignoring us but is in his own world.

Ok so if he's not socialising, is hyperlexic, has trances where he zones out, is resisting instructions and social norms and is rigid in routines do you think he might need an assessment for ASD?

@PritiPatelsMaker we did have a two year old review which flagged high scores which indicated ASD traits. Then we went for a SOGS assessment which was normal for his age, although I'm a little confused as to how this works as DS is not delayed in development in any stretch of the imagination, so I wasn't really expecting a referral off the back of the SOGS assessment as it was more about his development than anything?

Shameless bump

My son is 3 30 April and hasn't mastered toilet training, in fact all the parents I know with boys a similar age hadn't mastered it at his age - I am going to really try later this month.

I wouldn't be too worried about not being toilet trained. I would probably be more worried about the going into trances and stopping role play. Might be nothing or just a phase, but worth giving the HV a call.

Thanks @Thea91 that's reassuring to hear. I can't fathom as to how we had mastered the toilet training only to go back to square one but perhaps that's normal.
We've been to the HV to discuss the role play, trances/zoning out where DS completed a SOGS assessment which showed normal results although this mainly focussed on development which doesn't relate to any of our concerns - but was advised that he won't be referred due to not being developmentally delayed so no luck with that avenue.

Have you done the MChat Test @Appletree213

I know it can be controversial but I think that it might be worth doing.

@PritiPatelsMaker I've just completed, it returned a medium risk result - score 5.
Conscious if I raised this with HV, they'd say the same thing as previously which is paed would turn us away and not accept the referral as we don't really qualify.

I'd ignore the HV then and go straight to the GP. Take the results with you and ask fir a referral for assessment.

If you ask in the SEN section you might get some good support and information.

I agree I would speak to the GP. In my area you can self refer as well, although not sure how you go about it . I'm in the west midlands .

He could just be going through a phase but best to get checked .