PCOS or endometriosis?

Lauren • Married August 2014, boy mom, first 💙 born July, 2016, #2 💙 born December, 2018.
I had my first appointment with the fertility doctor today. After reviewing my chart and history, she mentioned these two problems being up on her radar. I have irregular and long cycles (27-40 days), seem to ovulate each cycle but sometimes very late, and have very very heavy and painful periods (although the last two since my mc weren't too bad). She did an ultrasound and there were no cysts on my ovaries, but she said that doesn't rule out PCOS.  Any of you ladies have either diagnosis? How has it affected your fertility? I'd love to hear your stories.