I've very recently started doing some Kundalini yoga for a change from my usual asana practice. Early this morning, I was simply doing the warm-up exercises, just finished the Sufi grind, and applied mulabandha - felt a lot of heat in the head and vibration, then wham! Gone. Came back to a sudden jumble of thoughts - 'that doesn't feel right' kind of thing, a bit of anxiety - and I lay straight down in corpse. Felt really shaky so stoped the routine and made myself some tea.
I've done this routine a couple of times and never had anything like this happen. I didn't faint, because I was still sitting on my cushion when I 'came around'. Still feeling the effects in both legs a half an hour later, so I'm holding off meditating for a bit longer.
Recently I've noticed that there's a fair amount of involuntary breath suspension going on in SBP - and I notice I'm (again involuntarily) doing SBP during DM. As soon as I realise that's happening I stop it, and simply return to the mantra.
I did a home AYP retreat for 3 days last week, and it all went fine. Practice has been really stable of late, so I'm trying to work out what's going on. Any thoughts?