I think it would be a good idea to get a second opinion.
Pain during intercourse is never to be ignored.
It is always smart to listen to that little voice inside your head; you know your body better than anyone else.
Don't be discouraged by the lack of concern your current doctor shows.....you keep pushing until you get answers.
A gyn/oncologist would probably be the best person for you to see, as women's reproduction track is their area of expertise. Your doctor shouldn't have a problem making a referral. If she does, get copies of your test results, including the info about your cyst, and make your own appt.
Don't give up.....you have to be your own advocate when it comes to your health.
Keep us posted.
You know your own body. This is not normal. Go to an onc/gyn.
You are young, but just going by your age isn't a diagnosis. If you are not an assertive person have someone that is go with you. Please make the call. Hang in there!
Pelvic pain is not normal, but it is highly unlikely that it is due to cancer. It sounds like you most likely have what's call endometriosis which causes pelvic pain for hundreds of thousands of women. An endometrioma or chocolate cyst is a cyst associated with enodmetriosis as well and these generall have to be drained or removed. I had endo in my late 20's and had to have it removed via 2 surgeries, but it did bring me relief. The other condition that can cause pelvic pain are adhesions (scar tissue), which can be a result of pelvic inflammatory disease, endometriosis (as it heals and then comes back) or any surgeries. I would seek out a Dr. who knows more about endometriosis otherwise they are just going to tell you everything is okay when it's not.
All my best to you sweetie and I know how you feel.
I hope you listed to the other posts. A cyst that big on your ovary can be the start of something - you are young but that doesnt mean you should ignore what your body is telling you. Not sure if you are underweight but that can affect your getting your period, but most likely the cyst or tumor on your over is stopping your periods. Get a pelvic abdominal sonogram or cat scan and see what is going on - you may have a cyst lower abdomen too and the fatigue can be anemia. Get to another doctor for another opinion and even an internist will check into your symptoms.