I was mowing my yard close to a tree when I felt a sharp pain like I had been poked by a needle. I did not see any bug nearby. I looked at my left arm and noticed I had a group of welts. I began to feel itchy right away so I went inside and scrubbed the area well with soap and water and took Benadryl. I am no longer having pain but feel like my arm is a little heavy and a little numb. I still have a few welts but they look less raised.