Even though CARRIE UNDERWOOD says there's no bad blood between her and TAYLOR SWIFT . . . the British tabloids would like you to believe otherwise.  And they may have a point.

There's a video from the Grammys showing the audience giving Carrie a STANDING OVATION after her performance.  But when you zero-in on Taylor, she's sitting on her boney butt and clapping her hands.

Obviously, this doesn't prove anything . . . and that moment represents one brief instant of the standing ovation.  (I mean, Taylor could have already stood up and then sat back down . . . but it sure doesn't look like it.)

Here's the photo.  And here's the video of Carrie's performance.  Forward to the 4:22 mark to see Taylor sitting while everyone else is standing.

One last bit of Taylor Swift nonsense.  After Sunday's show she posted an Instagram photo of her cat . . . and she wrote, ("Video shoot early tomorrow, so my Grammy after-party situation looks like . . . ")

instagram/taylor swift