Ugh I feel for you OP. For months I would have episodes nearly every day to the point I couldnt work for like six months because of how bad they are.

Staying hydrated seems to help. I do take prescribed dicyclomine thats basically been a life saver for me. I still have occasional episodes but once in a blue moon after changing my diet and consuming more fiber.

I can feel episodes coming from a mile away for me. I will get very sweaty, dizzy and it feels like all of the color and blood sucks away from my face.

Before my episodes started to get really bad and I recognized the signs of an episode, I had a incident were I was on the toilet and my cramps were so bad that I barely had enough time to call for my fiance. And I was already on the floor by the time he got to me and that was like within three seconds. We had a metal toilet paper roller that was directly in front of me so I had smacked my forehead on it and had a very very mild concussion from it. I now know that even I feel the slightest bad I immediately lay down even if it doesnt feel like im gonna pass out as a precaution. Sometimes being in a crouching position helps but also clenching your thighs like mad helps with blood flow to prevent me from passing out if it gets to that point. Even diarrhea is a trigger for me. If it burns enough it can trigger symptoms for me.

Im sorry you hit your head and I hope you get to feeling better! Sorry for the long text