Endometriosis.... help anybody?

ok this is kinda long, but i gotta fill you on everything in order to get a good answer. And last time i asked a question somewhat like this, i gotta bunch of "doctors" answers and they spoke in their lingo and it mad no sense to me. So try and make your answer as simple as possible please. ok i have had ovarian cyst on and off for 3 months now. The amount of pain i was in though led my doctors to believe i might have endometriosis. They thought i had this when i was 16(i am now 22) but the pain wasnt enough to bother me. The case is different now bc the pain does interfer with my life and it sux! I have a laparoscopy scheduled for April 21st. Today at 3:oo in the afternoon i ended up in the hospital bc of the pain, last i heard though i had two cyst on either side of my ovaries. So i asumed the pain was from the cyst. After 8 hours in the ER i found out my cyst are gone. The radioligist said that my endometrial lining was thick and swallen, but of course they couldnt give me any real answers. So i left the ER with out any good advice or reasoning for my pain. Can anyone tell me what thick or swallon endometrial lining means, and does it soumd to you like i have endometriosis. The pain is in my back and pelvic area, and they are extremly sharp but short. hope that wasnt too confusing. I apreciate any input or knowledge.