Abortion and PCOS...Did I do the right thing???? Please help me!?

I am nineteen years old and I just got an abortion...wow... it has been four months and it is finally coming down on me, I suppose my mind did a good job of blocking it out. But I am realizing that I would have been showing by now... the gift of a child that I vacuumed out... that I PAID to have vacuumed out for CHIRSTS SAKE... OMG WHAT is wrong with me???? I had a BABY inside of me oh my god... I was only four weeks along and the only reason I chose abortion is because the doctors all told me the baby would have probably died anyway (I have Poly-Cystic Ovarian Syndrome and my uterus has a scar inside of it because of this). If anyone knows what PCOS is and what it does to the body than you will understand why the doctors told me this. My thought was that I would rather get an abortion than miscarry and bleed my baby out if it was going to die either way, but the "what if's" are killing me. What if my uterus could have supported the baby? Am I just a murderer? Did I just kill a tiny child?!?!?! I am hurting so bad what if it survived??? The doctors told me my life was at risk if I choose to continue the pregnancy as well, but was I being selfish? I am the idiot who was not careful enough with , so did I punish a tiny baby for my own mistakes? I am very pro-choice but it is different when it is your own child.... and I guess I just want to know if I am a murderer? Did I destroy something beautiful? Even though my life and the life of my child was at risk, should I have at least tried? Please be kind, I am already breaking up because of this, but please give me your opinion. Because of PCOS I may never even be able to get pregnant again in the future, I had to get my right ovary removed for Christs' sake because of PCOS, so this is a huge worry for me... did I do the right thing? OR did I PAY to have the only preganancy I might ever have vacuumed out?? Oh my god... please help me.