For amphetamines at first I got nauseous and tunnel vision, then I had some sort of seizure(?) and woke up in a pool of vomit about 15 minutes later. Don't remember my dose but it definitely wasn't 10 grams. ODing on morphine was mildly pleasant almost, like sinking forever. Then I was found and I got hit with narcan. Realized I hadn't really been breathing, then nausea and suffering like I've never know. If you don't get revived I reckon it wouldn't be too bad on the way down to the end. (This was roughly 500mg of morphine)