Hi Leo,

I think you kept it too short to stimulate responses What is your practice?

If it is vipassana, I'd strongly suggest to stop any periodic movements. It is a type of piti/rapture, side-effect of concentration, one of the "corruptions of insight" (see e.g. here); it is called corruption as it effectively prevents progress, being followed instead of deconstructed.

Medical issues are not uncommon, that's a part of being alive whether one meditates or not, though some extras can be (probably) induced, healed or prevented by meditation, especially in retreats.

There is no need to look for the cause (Sallatha Sutta talks about that), anyway. Use common sense to deal with the condition conventionally (doctors) but also watch your reactions to it (annoying, wanting to run away from it) as a part of your practice.

Let us know how it went, good luck