freaking out ab breast cancer while pregnant

i am almost 20 so i’m young. i am also pregnant. right when i found out i’m pregnant in september i found a breast lump and got it checked out. my doctor said it’s a cyst and didn’t feel the need to do further testing. well recently my other boob has gotten weird white bumps on it. i’m not sure how to explain it. kind of like a long line that looks like a hive. and i’m freaking out that i have breast cancer. it’s all i can think about day and night. idk what to do.