I'm feeling a lot of pain in my right breast, especially when I press on it. It also feels really hard, kind of like a gland. Should I be worried about this, and what could it possibly mean?

Changing hormone levels can cause changes in the milk ducts or milk glands. These changes in the ducts and glands can cause breast cysts, which can be painful and are a common cause of cyclic breast pain.And there are many other factors also .So please visit gynae for further needful investigation and evaluation