Falconloft says:
Although there is no mechanical effect to losing Stability until your pool goes below 0, many players enjoy roleplaying the shocks and edginess of a terrifying encounter. Herewith, then, a few guidelines.
1-2 point loss: You might twitch, or stutter. Your voice could rise a bit, or you could Very. Explicitly. Stay. In. Control.
3-4 point loss: You might have to stop a bit and hyperventilate. You’re blinking a lot, and maybe sweating, too. If you talk, you might
run away with your own words. Keep doing something comforting – rack the slide on your shotgun, hum the Miskatonic fight song, that kind of thing. That will see you through this.
5-6 point loss: This is serious. You may go into a little fugue state; déjà vu comes over you, or you get "frame drop" and miss a couple of seconds. Nothing fatal, no, you’re still good. Nope. If you’re talking, you might call out some encouragement to your mates! They’re probably not doing near as well as you! If you’ve got a pre-existing condition, say a phobia or Shell Shock (see p. 77), you’re hyper-aware of anything that might trigger it.
7-8 point loss: How are you not shaken yet? You’ve almost certainly gone into adrenaline shock; your peripheral vision is gone, and your hands and feet are cold. You may babble personal confessions ("I’ve always loved you, Tom") or just shout incoherent threats. If you can make Interpersonal abilities work at all, they work more through fear of what you might do next than anything else.
Awesome thanks for letting us know what this means I am thinking my next move possibly just relaxing at the moment :)