Hi welcome to Health care magic forum, It is good that you are recovering from glandular fever
, and comfortable with the treatment, cheer up in a couple of days you will be fine of the joint pains
Regarding MDMA , methamphitamine, whatever the abusing drug may be it will have bad effects on the body and brain, naturally during convalesence the body will be weak, so naturally can't tolerate the effects of methamphetamine
The joint pains, it is the process during convalescence of the some fevers. It could be due to diet we take during fever, like potato, othertubers, egg, chicken, seafoods etc as they cause the increase in pains which are already there. So if you are taking stop them till you get relief of pains.
Wishing for a quick recovery and thanks for calling.