Red reoccurring bump

I’m a 34 year old mom of two teens. I keep getting a red bump that looks like a big bite on my left breast. It itches and only stays for half a day then disappears as quickly as it appeared. I have had it appear once or twice a week for about a month now. It’s always in the same spot. I sent my doctor a description of what was happening and a pic. All she did was prescribe a cream for what looks like a big bite. But it seems strange that this bug would bite the same spot every time. My breasts don’t seem to have any other real changes except for itching. Anyone think I should be concerned ? What would my next step be?