What Causes Bruising Around The Mole Removal Site?

Hello, I have had two questionable moles removed and the results came back as Dysplastic, one was Atypical, not sure what the difference is. During my last scheduled visit, my doctor removed another that went from 5 to 8 in diamater. My question is why do I have bruising around the area? I did not see any bruising around the other ones when they were removed? Is this a sign of something that I should be aware of?