Thank you for posting in Doctor spring. Com.
As per your description, it looks like Fibroadenosis. But, cancer has to be ruled out as you do not have children.
Initially, get an Ultrasound or Mammogram of the breast.You will get an idea about the swellings, extent and nature of the swellings.
Next test is FNAC (Fine needle aspiration cytology), which confirms whether the swelling is Cancerous or not.
These two tests will confirm the diagnosis.
Please get them done as early as possible.
If you come back with above reports, I will clarify further.
Wish you good health