As other's have stated, likely an anxiety attack. If i had to take it a step further and be presumptuous, I think the activities you mentioned would give a glimpse into fear of losing control. Perhaps, that fear causes anxiety? One other consideration, is that be wary of packaging labels as I am sure you know from workout supplements. In the Kratom world, I find the marketing very similar to marijuana which is also then very similar to heroin and cocaine.
What I mean is that almost every "drug" offers an "indica" version and a "sativa" version and a "hybrid" version. Kratom has the "red" strains for pain relief, chilling, blah blah and the "green" strains for "energy" and "focus." Interestingly, almost all of them also have the crossover properties of "euphoria" "feeling good" "uplifted" etc. I am not saying that there are not differences, but the marketing I think GREATLY biases user expectations.