Patrick Mahomes is headed to the next playoff round, but the happiest person in his household has to be his wife, Brittany ... who posted a crap load of photos with her new twin.

The mother-of-two and former college soccer star shared the pics from Saturday night's 26-7 Chiefs win where she posed with pop sensation Taylor Swift.

TS and BM hit a series of poses ranging from cute and flirty to downright silly ... and close friend and fellow WAG Lyndsay Bell hopped in for a couple pics too.

Mahomes made reference to their matching puff jackets -- emblazoned with the names of their footballing beaus on the back -- in her caption, writing "Twinning & Winning