You could say something along the lines of:
"Hey, Friend, what's so good about weed? Why are you always smoking it?"
If he's smoking it for medical purposes, then just drop it, but if it's illegal and he's doing it to "look cool", then I would further ask questions about it.
NAIL IN FOOT:
If your foot wound is bleeding from the nail, put a towel over it to stop the bleeding. Then use water to clean the wound. If you have any antibiotic cream, apply that and cover your wound with either bandages or some old pieces of clothes.
SWOLLEN TOE:
Raise and rest your foot with the swollen toe when you can. Put some ice wrapped in a towel on the toe for up to 20 minutes every 2 to 3 hours. Take a paracetamol if you can. Do not walk or stand for long period of times if it hurts a lot.
hope this helps and i hope you get better soon!
