The problem seems to be a massive accumulation of energy winding it's way up the spine, which then stagnates in the upper chakras.
In the weak kitten, it didn't make it past the solar plexus, epigastric, affecting the breathing and then that set off epiliform spasms that shut down the heart. You could smell the fecal breath - but the spasms clearly had a good function because the kitten shat - it was the spine waking up but the organs were already too weak.
In Burps case his breathing is affected too and his heart. The anxiety makes him cry for me all the time today after Hydrophobinum. Maybe 30 is too low but it's all I had. The energy probably made it up to his heart but accumulated there.
I had a sun headache after apis cm which hydrop cleared. So my accumulation was at the back of the head. Now, sleeplessness.