Armpit area feels weird. Muscle or what?

Hi Dr. I explored my area for the first time recently, and I noticed that there is a small area that I feel fishy about other than that. I have no symptoms or no issues. Absolutely normal with everything. It's just that I read something online about lymph nodes in the comfort area and started to explore my body started to feel weird about my armpits. I have attached a photo of my armpits. Please check if there is any kind of abnormality with it. I don't find any lump or bump anything. What is this raised up area in the armpit? I have anxiety and depression issues. It is making me very bad. Please help me doctor. I just want you to tell me if the raised area is a muscle or what? I am talking about the high raised potion in the second picture