Yeah we're all germanian.

In fact, Midgard was renamed Norway only after the Vikings had told the english that they had taken "Norvegen" to get there (norwegian for "the north path"). Then later on, we started calling our own country Noreg "Eg kommer fra nor, eg" ("From the north, I come"), and then later still "Norge" during the danish union xD
Fun Fact: You brits practically invented the name of our country

Pretty much.
"Vikings" are, by definition, exclusively norwegian. "Viking" is an anglicized version of the norwegian word "Viking" which means anyone who lived in either of the many "Vik"s of the norwegian fjords. Even the swedes weren't true vikings (they were "Sveafolk" from "Sveariket" where the danish name Sveariget --> Sverige (Sweden) is derived).
Last time I checked, there aren't any viks nor any fjords in Holland. Maybe modern-day Amsterdam is a unique exception in the "vik" department. But fjords are globally unique to Norway and Alaska (scars from the ice age).
That's nationalistic folk etymology, nothing else.
Alfheim, on the other hand, is thought to have been a small kingdom located somewhere along the G?ta ?lv on what's now the Swedish west coast, possibly in Bohusl?n (which belonged to Denmark-Norway up until the mid 17th century).
Also, "viking" is not a Norwegian word, since there was no Norwegian language back then. It's Old Norse. The Danes were vikings just as much as you were.
And it was not used as a name for those who lived along the creeks/vikarna and fjords. Viking was originally a verb, not a noun, and was most likely used to mean "to plunder/practice piracy".
The word probably stems from the fact that viking ships were able to navigate in creeks/vikar and other very shallow waters, something which most ships back in those days could not.
The Swedes were also, technically, vikings since we went a-viking, but we were usually called varangians. Vikings went west, varangians went east.
When you were pillaging and colonizing the British Isles and other parts of western Europe, we were pillaging and colonizing Russia (in fact, the word Russia comes from the Rus people of eastern Sweden and southwestern Finland) and the Byzantine Empire.
Edit: Oh, and Swedes/Svear was just one of the Swedish tribes. There were also the Geats, the Gutes, etc. But the Swedes eventually conquered the other kingdoms and created Svea rike/Sverige/Sweden.