Thank you to everyone who responded.
I agree with both of the ladies. You need the us to see if anything is going on in there, and get the treatment you need. You are in my thoughts and prayers. Godspeed
~Tascha
Another possibility is Pelvic Inflammatory Disease (PID) which might be treated by medication.
There could be any number of reasons for the pain and swollen pelvic region and having the US is the best way forward. Unfortunately, you don't state your age or if you're having any other symptoms but if you do have a cyst then please remember the majority of cysts are completely harmless and some even go away on their own without surgical intervention so please don't worry.