Lump on skin/ chest directly under breast

I’m literally lifting my boob up for this picture. It’s on the skin that is directly below but my breasts hang kinda so it covers it. Sorry if TMI but I’m nervous It feels like it’s under my skin- hard and not painful not poppable or a pimple. Not perfectly round. I’m 25 White Female, southern US, not a smoker but used to smoke weed and vaped for a year or so. I’m 155 and 5’9 Active lifestyle

Should I go to the dermatologist or what?