i was stung on the left side of my scalp exactly a week ago. the area of course was slightly swollen and kinda painful the rest of day. the next morning swelling was gone but still a little painful, but i noticed three swollen lumps behind my left ear. i'm guessing these are lymph nodes and somehow my body is reacting to the sting. no history of allergic reactions to stings or bug bites but haven't been stung since i was a kid. lumps lasted through the weekend so monday i started taking benadryl twice a day. it has done nothing for me except make me feel light headed and tired. lumps are still there. should i be worried?