I don't see it that way. It is VERY rare that the president's party gains house seats during his mid-term and also rare that the president's party gains senate seats.
In terms of house gains, Obama lost 63 house seats in 2010. Trump only lost 39. The last time the president's party gained seats during the mid-term (either house,) was 2002.
Pretty chart, here: https://fivethirtyeight.com/features/wh ... et-redder/
I think this was a pretty mediocre showing by team Blue. It was certainly not a "wave."