5 cm. left ovarian cyst 10 yrs. after partial hysterectomy

I was wondering if anyone else with similar cyst have experienced what I am going through, it has been so painful for many months.  Unfortunately the groin & back pain pain started in august and then my buttocks thigh. so after being treated for a few months for sciatica my mri and cat scan both showed a 5cm. cyst. on my only remaining left ovary. My dr. is pretty sure this is what is causing my ongoing pain buttocks and groin, back especially but sometimes i even get pain behind my knees so weird. I look about 4 months preg. and on a frame of 125 so needless to say comfy pants have become my new style. I didn't have a reg ob/gyn for years and they had me scheduled for january but my wonderful dr. has gotten it moved up to dec. 20th. I am having lots of problems going to bathroom, like full bladder constantly and very irregular movements which at times are very painful in my lower stomach.  the mri says unilocular adnexal cyst, and the cat scan says multilocular. can someone please help me understand these terms?  is it possible that the cyst could be effecting my sciatica nerve? one day my left leg just completly came out from under me. i went to the chiropracter for 9 visits but didn't help. any suggesions ladies???? i feel like i have become one with my couch and am starting to really get depressed about it.  would love to hear from you lots. be really appreciated