I have also experienced bad muscle tension from cactus. For me it is worst in the arms and legs. When it gets really bad my arms feel swollen and tight and they tingle. My legs tremor and shake, like a never ending muscle cramp that causes the muscles to twitch.
I almost always get nausea and vomit when the muscle tension is really bad. For me the muscle tension and the vomiting, this is a sign that the dose is very high. These are the trips that I see lots of visuals. Usually I am dazed and laying down for long periods when it gets like this. For me it has taken big doses of Bridgesii to get there, 2 feet or more of cactus
Maybe the cactus you are using is very potent, and you are taking a bigger dose of mescaline/alkaloids than you realize? Also, because you have been eating so clean you should really feel the effects of the cactus, especially on an empty stomach.
IT WAS ALL A DREAM