I was 10000% sure I had ovarian cancer a few years ago (I was 28 at the time). I had a big - 11 cm, think "small grapefruit" - complex cyst, and a smaller one on the other side. I had EVERY symptom in the book - pain (it was miserable), bloating (my stomach got big fast - I couldn't even lie on my stomach; it was like lying on a Pogo Ball!), stomach problems. My CA125 was 249; highest "normal" value is 35. I was referred to a gyn/onc for the surgery because it was their area of expertise. Naturally, that scared me even more. Even though all three doctors I spoke to about it put my odds at it being benign 95-98%.
After all that, it was in fact endometriosis, just like the oncologist predicted. With my hypochondria and googling, I had convinced myself it was cancer, but it wasn't. My odds at it being cancer were astonishingly low, even with more specific indicators than yours, and when I googled all I found were horror stories.
Talk to your GYN about it. Chances are he or she will tell you it's a benign cyst or something like IBS. But you really don't need to get worked up just yet, because the odds are VERY low that anything serious is wrong.