First the hope: I was in about your same position about 25 years ago. I don't remember the exact measurements, but my gynecological oncologist (hereinafter known as GO) said that my left ovary had a mass that was the size of a grapefruit, and my right ovary had a mass that was the size of a cantaloupe! He was so impressed with the size of the cantaloupe one that he actually took pictures of it before removing it (I still have the pix around somewhere).
In addition, my CA 125 test (that's the test that looks at the amount of cancer antigen 125 hence the name you have, which is a marker for ovarian cancer) was close to 200 (normal is less than 35). Before I finally got to my GO, everybody, including doctors, was totally freaked out by my symptoms, the size of my masses, and my CA 125 numbers.
My GO, on the other hand, was blase. He said that it almost never was cancer unless the CA 125 was over 500, so he was fairly certain that what I had was just ovarian cysts.
And indeed he was correct.
It was more than a month before I finally had the surgery to remove them. (Remember, in my case I had met with my GO not that long after diagnosis and he had reassured me, so while I was still concerned, I was no longer panicked.) They were only cysts.
You said that you had some bloodwork done. I assume they did a CA 125. What was your result?
Now the advice: it's never a mistake to get a second opinion. And no, you're not overreacting. When something like this happens, even if it turns out to be nothing, it's never an overreaction!
If you haven't even been in to see a gynecological oncologist yet, and you can't get in to see the one you were referred to, maybe you do want to make an appointment with another one. Just in case, it won't hurt to either be reassured that they're probably cysts or the GO will want to do surgery immediately, if they think they're malignant. Either way is better than the limbo you're in now.
I admit, the fact that no gynecological oncologist has actually checked you out yet and, believe me, you want a gynecological oncologist for this! so no one is actually sure if these masses are malignant or not, yet they're still dragging their feet, is more than a bit concerning.
I have lots more advice, but this is already a wall of text so I'll end here. Let me know if you have any questions (or want some more advice!); I'll be happy to answer and help in any way I can.
I'm rooting for you!