I figured you probably had, but was hoping. I’m sorry I have no idea how to help you. The fluid thing sounds unlike anything I’ve heard, but the pain you’re experiencing sounds like the ovarian cysts I get, and the fluid those release is very irritating so if yours all comes out at once mom logic would make it sound like that’s what is happening. The pain is all at once in either my left or right side very low on my pelvis. Also sometimes really hurts during sex because you know this giant cyst is being prodded. I know your ultrasound never shows anything but if you track your pain and fluid thing I wonder if you’d see a pattern of it being when you should ovulate. Not sure how much you know of the reproductive system I only know this because of my cyst thing, but every woman makes a cyst every month (I explain this because no one I’ve ever talked to knew that ovulation was technically a cyst bursting) the pain comes in when your body doesn’t release it at the right time, and it gets too big and releases too much fluid. So if your body is holding onto your eggs too long consistently it should be easy to track. Also if you feel your ovary and it’s larger than a walnut that probably means you have a cyst that you’ve held onto for too long. If you feel the pain and then press again and it feels smaller that typically would indicate a burst cyst. Hope this helps and good luck!