The persisting red mark on your foot is the remnant of the haematoma(blood collection) you had as a result of cupboard falling on your foot. This will go fade and graduslly away in a matter of days. I hope you got your foot xrayed and there is no bony injury. If there is no bony injury, the pain is because of soft tissue injury
which will also go slowly. You should take some pain killers, apply a gel and crepe bandage and take rest. To completely rest your foot, you masy wear a posterior cast for a few weeks. If there is a fracture
, you need to wear a plaster for which you should consult a orthopedician.