What are the difference in symptoms between endometriosis and fibroids?

Complicated: This is a complicated question to answer, but I'll give you some ideas. Fibroids are muscle tumors (benign) and when they are small, so long as they are not invading the lining of the uterus, typically don't cause any symptoms. As they grow they cause pain and pressure. If they invade the lining (even a little) they can cause bleeding abnormalities. Endo causes pain, cramping, irregular bleeding.

Can't always tell: Endometriosis and fibroids are common gynecological conditions in fertile women and often are asymptomatic. When large in size and/or depending on the location, fibroids can present with heavy menstrual bleeding and/or bulk symptoms - pelvic pressure/pain and urinary symptoms. Endometriosis symptoms include chronic pelvic pain, dysmenorrhea, menorrhagia, vibration pain, dyspareunia and dysuria.