Late Last Week I Was Stung By A Large Number

Late last week I was stung by a large number of bees. The swelling everywhere has since gone down, but one sting was on my cheek which hadn't swelled that much initially. Two days ago though I mowed the front lawn and my face got rather red from the heat and that evening I noticed some swelling in my cheek where I got stung. It is gradually spreading up towards my eye. I'm taking pain relief and diphenhydramine. Is this a secondary reaction?