I Am A 47 Year Old Woman And Have Been

I am a 47 year old woman and have been eating shellfish my whole life. On Saturday night I had fresh lobster and my face got very red, hot and itchy. This lasted for over a day and I had very little relief from Benadryl. I am assuming that I have developed an allergy but am trying to understand if I am potentially going to have more severe symptoms if I continue to eat lobster.