It's the caffeine that did it, I"m sure. SWIM has used mescaline with elemi oil before and the trip experience was just like you said, but there was no headache or body pain. SWIM has not been too fond of mixing caffeine with elemi oil at higher doses. He's gotten a slight headache from that combination before. At lower doses it mixes well with caffeine, but not at higher doses. SWIM is assuming it's the eucalyptol causing it, but maybe it's the elemicin. My advice is to avoid coffee while taking a large dose of elemi oil.
When SWIM once took mescaline after an elemicin (elemi oil) peak, the mescaline was SUPER STRONG. The mescaline trip came on fast and peaked fast and was gone fast, and then the elemicin took over. So there's some drug interaction happening for sure with mescaline.
It's very possible that the elemicin interacted with the LSA containing seeds and even though the trip from the LSA containing seeds was fading, the elemicin could have boosted it a lot like it can do with mescaline. But then the guy says he's pretty sure that wasn't the case. Until it's tried without taking LSA, we won't know for sure if it was the LSA being boosted and altered or not.
Now if the LSA containing seeds are being boosted like mescaline can, and that guy simply experienced a synergistic boosting from the LSA and elemicin combined, then we have a new way to boost the effects of other general psychedelic other than using MAOIs and datura. It seems to me that this could prove to be a great admixture. SWIM likes elemicin more than datura, and it seems safer than using an MAOI (but this is just an assumption).
If you can take LSA containing seeds and elemicin and get an LSD-like trip from a small dose of each, that's pretty exciting I think. SWIM will have to try that in the future for sure.