I have tried codeine like 4 times, the first one was a CWE so I thought I could have messed up the whole thing. Yesterday I took 120mg + 50 mg of promethazine and didnt feel anything at all besides being sleepy, most likely from the promethazine. What would happen if tonight I took 300 mg? In case I dont metabolize it, would it still harm my body in the same way that it would if I could metabolize it?