AMT is NOT legal, perhaps you mean 5meo-amt. Doses are quite different. My one experience with 5meo-amt was terrible nausea on the way up, terrible headache on the way down, an intense, highly visual trip in the middle, but it lasts longer than eight hours. Sounds like what you had was actual AMT, it's illegal now, good luck finding anymore. I never got the chance to try it, regret that, not so much because it sounds more interesting than lots of other RCs, lots of them feel sorta like a cross between cid and E, but if you look at the structure, it is the trytamine version of alpha-methyl phenylethylamine, usually shortened to amphetamine.