Your ankle is not necessarily swollen..  THe same thing happened to my husband
from a bee bite.  The problem is that ice will not help this late in the game
Start taking benadryl and go to the doctor.  You could have the beginning of
cellulitis which could be dangerous.  He will more than likely give you a shot
of prednisolone, an anti inflammatory.  He will also tell you to prop it up.
This is due to a delayed histamine reaction to your bite.
Paula