My quick look at Swedish exports shows that the largest export is finished equipment at 14%, fuel exports at 7.1, 4.8% wood and paper, 3.6% iron and steel, of which I'm sure a lot of that equipment is made. 3.4% plastics, which is just oil in another form.

It looks like you're right and their oil exports are all import/export rather than domestic, but that's still a good bit of mineral wealth.

Yes Sweden has non-trivial mineral resources, but nothing like e.g. China, Russia or Australia though.

The Scandinavian social programs are funded by high taxation. It is mostly a result of political prioritization, and not a windfall of natural resources.