My myoclonic jerks (like an electric zap from head to toe) started within an hour of my accident (head and neck injury). I still have them albeit to a lesser degree (not as ‘intense’) more often at night but still get them through one limb or another during the day. They appear much much milder now though, 10+ years later and barely disturb me, if at all.
I think part of our problem is that we release too much adrenalin when something like this happens (yes the ‘fight or flight’ mechanism does overdo it somewhat). I can’t get to sleep for ages if a noisy car goes past – how daft’s that! When did your myoclonic jerks start ?