Hi, welcome to the forum, this can be a insect sting due to wasp insect or bee. With insect sting, the symptom varies from minor bite pain to life threatening anaphylactic shock. The types of manifestations encountered are local reactions, systemic allergic reactions, toxic reactions, and delayed reactions.
Local reactions are the most common type of response to insect stings and are seen immediately, and include swelling, erythema, and pain, affecting areas that are seen with the sting site.
You will have local reaction for now and need to be managed by anti histaminics and if required steroids against prescription. You need to keep watch for another 10 days and consult physician if you develop joint pain, fever etc. which is a sign of delayed reactions.
I suggest you to consult dermatologist. Take care and regards.
could be a bee sting or something but it sounds like you may be allergic to whatever it is