I would suggest that you stop most or all of the other supplements, if you haven't already, and try just ALA every 3 hours for 3 days. Then you can see how you feel while doing that. If you feel worse (tired, maybe a headache or strange feeling in your head, and a variable number of other side effects), then that is a pretty good indicator that the ALA is removing metals. If you feel no change at all, then that would suggest it's not doing anything and perhaps heavy metals are not your problem (or it could suggest that ALA is not effective for whatever metal or toxin is causing you trouble, if any).
If you react to chelating with ALA, then you could add in supplements which help with chelating. I would be careful about using too many supplements since they can cause their own problems and confuse us as to what is actually working.