Despite having pulled themselves back into the game through a Dan Burn own goal, Spurs were beaten by Alexander Isak’s winner.
Even with 66 percent possession and 20 shots, Spurs could not fashion more chances to score.
On his Instagram story, Bissouma wrote: "Not the result we wanted but will keep going again thanks fans for the support and see you after the international break #COYS (white heart emoji)."
Manager Ange Postecoglou told reporters: "Very similar I guess to our first away game when we controlled it for the most part, nullified most of the threats that Newcastle have.
"It's obviously a difficult opponent here at home. The crowd create a pretty strong atmosphere for the home side, little things go their way but I thought for the most part we handled that really well. Then we gained the ascendancy in the game and we just needed to kill it off and we didn't and a disappointing second goal.
"I thought we switched off a little bit but the game should have been well over by then. So, another sore one unfortunately where we haven't got the rewards for our play, but ultimately it's three strong performances from the first three games. The results don't reflect it in that way."