That could be chill blains ie due to cold
exposure you have developed vesicle ie fluid filled swelling over the pinna.
You must get it examined and punctured by ENT specialist
and take adequate antibiotics.
As pinna swelling and infections are very difficult to treat in addition the condition itself is very painful.
you may also need anti inflammatory medicines and daily dressing .
Do take care while sleeping that the pinna is safe and does not get infected by the pillow cover or bedsheet