I have same problems before, and never find any cancel transaction from Metamask wallet. So the only way to do just sent 0 balance in same nonce number from Metamask with higher fees. But this is not to cancel just to makes your previous transaction being confirmed.
Here my thread when i got similar Issue.
https://bitcointalk.org/index.php?topic=5184484.msg52451444#msg52451444Thank Sir, I did fix this, I trying nonce = nonce pending lower
p/s: I'm so sorry, My english verybad.
Thanks for coming back and saying that was the fix (most people don't and it helps for guests when they get stuck to know the fix).