Worried about 5 month long RLQ pain - what could it be? (Dx with 4 auto-immune diseases)

Hi, I (24 y/o female, weight: 65 kg, height: 185 cm, no smoking, no drinking, no drugs, outside USA) have been experiencing RLQ pain for around 5 months now and I am starting to get extremely worried about what it could be and if it is dangerous. It started with heavier periods, with painful cramps and extreme blood loss. Then on an ultrasound they accidentally found a 6 cm cyst on my right ovary, that on a follow-up vaginal endoscopy went away on its own. The gyneacologist suspects it was a corpus luteum. However, I still experienced these painful periods and most importantly a very sharp pain between my belly button and my groin (right side) that was so bad I could not sleep. My GP suspected endometrioses and offered me the oral contraceptive, which I have been taking without a stopweek. This eased the pain (and the periods), but I am still bleeding through it quite regularly now and since a few weeks the pain has returned, and now its constant. At the same time I have a hard, small lump in my groin that seems unmovable and not painful. It has been there for 4 weeks now and has not changed. I also have a smaller lump in my left groin and a really small one in my neck (almost unnoticable). I am extremely worried and cannot place this weird heavy feeling/pressure in my RLQ, as well as the lumps. A bit about my history: I have IBD, PSC and AS, but I seem to be in remission of these auto-immune diseases. No weird stool, no weightloss or other symptoms. Only very low ferritine. I will visit my GP on monday, because I do not now which of my doctors to contact as I cannot locate the pain really. I am really worried I have cancer (ovarian, colon, lymphoma) or that it is something that is going to change my body. It can be so many things (a cyst, endometriosis, adhesions, kidney stones, infections, colon inflammation, etc etc) , but I was hoping to hear some professional opinions here. The pain is around the groin, but radiates towards the hip and sometimes also towards my lower back and anus.