Which medicine works best for severe menstrual pain?

Hello doctor,

I am a 28 year old female nurse, I have been having severe menstrual pain throughout my life, and sadly each year the pain increases. Since I was a college student, each month for all the four days of my period, I had to stay home lying in the fetal position, had to keep a heating pad on my lower abdomen and used to take some serious pills. I have seen so many doctors, and each one of them gave me the diagnosis of endometriosis. After I had done a deep search about this medical condition, I was not happy at all. I even tried contraceptive pills for six month, which reduced my pain but made me gain 19 lbs due to pure water retention. So, I stopped the pills, and the pain returned more aggressively.

Since I start working as a nurse, I am having problems to keep up with the working time during my periods. And my colleagues cannot always help me out to switch working days with me. So, I had a laparoscopy, and they found inflammatory things, but they could not determine what exactly it is. So, I changed my doctor and did an RMI, according to it they found some endometriosis tissues. And I also have a retroverted uterus. I am tired and sick of this issue, and lately, I started taking medicines to help me endure my pain. According to the latest doctor that I consulted, I have only two options, a medication called Visanne or an injection called Decapeptyl. I am terrified from both, because of there side effects and unknown results. And these will make my body go through menopause. Please help me.