Before we get into it.
You can also try just slowing way down for a bit and usually focusing on her pleasure over yours can help.
Even pulling out and licking her a little can do the trick.
This implies the root of our problem is mostly psychological.
Best of luck to all of you.
So when you feel yourself stiffening up, take some deep breaths, but make sure you breathe through your diaphragm, not just shallow chest breaths.