Property renovation advice needed..help

Please I just need some advice/clarity on my current situation! For context I live in the UK/ England

I purchased a house back in 2021 and it had a conservatory attached to the kitchen. In 2022 I decided to knock down the conservatory and extend the kitchen (I did not get any sort of planning permission as I thought because there’s already a conservatory which was built out it would be okay to just build over those foundations) I honestly did not think or know planning permission would be required for something like this (1st time homeowner)

Did I need permission to do this?

The conservatory was built over a manhole, when we built the kitchen we were not told by the builders about this manhole and were unaware of it. I have had a leak from my sink which we’ve had to address and is why I’ve just noticed this manhole…it’s inside the kitchen.

The kitchen was built over the same dimensions/ foundation of the conservatory but I had walls internally removed

What should I do? I feel I have totally messed up. Please someone advise me on the manhole as well as the kitchen being built

Am I going to be fined for the kitchen being built? Will it have to be completely knocked down? Can I get permission/approval after it’s been built?

Do I just leave it and hope for the best in the future? I have read somewhere if it survives 4 years after construction, the lack of approvals/permissions can be disregarded?? Someone help…I’ve put som much money into this kitchen I don’t want it to be ripped down