Thanks for telling us your situation. But may I ask, as a Norwegian myself, why do you choose to pay taxes in Thailand, since you already do pay taxes from your pension in Norway? I assume this is something you have chosen to do, and filled out all the needed forms for that purpose. Most retirees I know from Norway do not go through this, because it's so much hassle doing so, with all the paperwork before getting your refund. And then you are in best case status quo, or probably minus, with taxes and all the expenses you have had.
Now, I do know the 183 days rule, but as far as I know, Thai authorities never ask for this pension to be taxed by Thailand. And since you pay full tax in Norway, most Norwegians just let this be.
For me personally, the taxes are much higher in Thailand than Norwegian government deduct from my pension. So I just wonder. Why go through it.
But kudos to you anyway, you are doing the right thing. And the right thing, is what scares a lot of people in this thread, to start paying Thai taxes for pension income, and go through all the hassle for a refund. Norway do have the same tax double agreement as 60 other countries, but with some small differences.