You can do the cleansing, etc., but you should also just put it down and leave it for a bit. Don't work with it for several days (several, not a few). Sometimes, regardless of the type of work/reading we're doing, we simply overload ourselves by asking too much too often. So take a break and let yourself and it rest. I think you'll then find a better equilibrium with your pendulum.

(An aside: It's my bias that stones and such don't need "cleansing" or "clearing". I worked with such things for many, many years and never found the need once I released the whole cleansing/clearing idea. After that, things worked even better because I wasn't holding on to negative concepts about it. That said, it's my bias and I know many disagree. I believe nature takes care of itself, and unless manufactured (as many "crystals" are), they're self-cleaning. Ha! Kind of like cats. )