no pain, no itchin, i don't take any medicine and no past illnesses
Thank you Lorna, for the information,
The swelling is likely to be due to an allergy.
The cause of allergy is often not apparent.
Food is often a factor.
But it can occur from environmental allergens too.
Sometimes, bite, infection etc can cause it.
But you do not have any sore, pain there.
In infection the swelling would not subside so rapidly.