I had very similar results. I expected a high British Isles ethnicity with surnames like Womble, Holland, Harrell, Copeland, Wilson, Bendall, Sadler, Davis, Holt, but was reported as over 50% Scandinavian!
Although I have no paper trial to the Isles, everyone on my paternal line has a direct paper trial to colonial Virginia and colonial North Carolina. Everyone was born in those two states and nowhere else. These two states have high rates of Isle ancestry. Those surnames sound very Isles to me. They do not sound Scandinavian.
I also was reported as Southern European and Eastern European. That I expected. My mother's side is Hispanic and possibly Italian.