Last august I swore I had ovarian cancer. I had bloating, pain in my rectum/lower pelvic when I say heavily or walked, and my weight was jumping up and down. I had a pelvic exam and when my righ ovary was palpated it hurt so bad! I knew I had a tumor on it and I was gonna die.
well, I had 4 ultrasounds, regular and transvaginal and my ovaries and uterus and all those things in there were 100% normal! I had a small cyst on one ovary, but they are very normal and come and go every month. I even was shown the ultrasound photos and shown how normal they were.
I would ask for an ultrasound and clear all this worry up :)
Oh and get a new Gyno. He sounds awful..... I find women to be much more caring and understanding with these types of things because they can relate.