Very high doses seem to have little to no effect, not sure if doses should be increased or if I'm being stupid

ran a week at 600mg with basically no effects (holiday weekend, ate like a pig, gained 10lb of bloat). Now upped to 900mg ed and only feeling a little warm, some night sweat and heat around mealtime and a bit of lethargy. Body temperature is not increasing (98.3 is the highest I've measured it). Source is reputable but it seems like most people feel like they're about to die at 400mg and I'm over twice that and the worst I feel is about the same as if I had a big bowl of hot soup or something. What is the signal that dosage should be decreased?