Andometriosis & Endometriosis

I am 26 years old. I have 4 children. All boys, ages 9 weeks, 20 months, 3 years, and 4 1/2 years. They were all delivered by C-section. I had a baby 9 weeks ago. When the baby was 5 weeks old, at the onset of my first cycle since delivery, I began experiencing extreme lower back pain and sensitivity on my lower abdomen. I had a section for my delivery so my doctor had just looked at all of my organs and he knew everything was fine. My first cycle was so heavy and long he gave me estrogen pills to stop the bleeding. I spotted on and off after that but never began bleeding heavily. For the past 4 weeks I have been in and out of the hospital running test to find out what is wrong. He originally thought I had an infected uterus. That was obviously not the case because after 3 rounds of IV antibiotics and 1400 mg a day for 7 days the pain was still present and was becoming worse each day. I had several test such as blood work, urine, x-ray, ultrasound, CT scan and last but not least laproscopy. All in all the laproscopy told us what was wrong. Come to find out over the past 9 weeks since I had the baby I developed endometriosis and andometriosis, I had a cyst on my left ovary that ruptured and my falopian tube on the right was clogged and filled with fluid. My question is how can all of this happen in just 9 weeks? It is mind boggling. I have been given the option to try birth control or shots to put me into menopause but their is no guarantee these will work. My OB/GYN gives me no more than 12-18 months before I will have to have a complete hysterectomy. This is alot to handle, especially because I never had female problems before and now I am faced with this.