What is the reason why i have sharp pains in my breast?

Get examined: One possibility is caused by estrogen either in cream, pills, or birth control hormones. Whatever the cause you need a dr to examine your breast and probably a mammogram and ultrasound of both breasts to rule out masses, cysts or infection. Even herpes zoster may cause abnormal sensation in one breast for few days before the rash shows up. Review your medicines.

Unknown...: Without an examination and detailed history this is difficult to answer in this forum...Please go to your doctor and get a thorough evaluation!