I'm a female in my mid 20s, what are symptoms of high estrogen levels? are high levels bad?

It varies: Very high estrogen levels may be a sign of ovarian or adrenal tumor. In general estrogen levels vary with the menstrual cycle. Too much estrogen may cause symptoms such as breast tenderness, weight gain, bloating, water retention, irregular uterine bleeding, headaches/migraines, abnormality of the uterus (hyperplasia) which can lead cancer. Some literature suggests anxiety and depression, etc