Setting - Different effects each DXM trip?

[aaronitotheburrito]

swim has been using dextromethorpan for about a month. swim uses it to constantly about once a weekend but swim has done it twice in the past week and about to do it again tomorrow night for the last time in atleast 25 days.swim feels addicted
but back to the question
everytime swim uses dxm its different not completley different but different somewhat
sometimes swim wont feel much of a stimulant coming on instead hell jsut feel out of his body and thinks he is something hes not
one trip swim thought he was a troll shaman from world of warcraft
swim wants to know if anyone else has this
also is it a very bad idea for him to up the dose and do 450 mgs 30 capsules tomorrow.