Happy but Jealous for my sister in law

Hi ladies I had to get this off my mind cause it has been bugging me. My sister in law is pregnant with her second child and when we found out I was happy for her but deep down I was a bit jealous since recently I had to have an emergency c section at 29 weeks for my twins due to 1 twin having his sac broken for almost 2 weeks and preeclampsia and they are currently in NICU and there is no date of when they are able to come home since they still have a lot of growing to do. But my issue is that I was not able to enjoy my whole pregnancy and I got my tubes tied so this was my last pregnancy. But it’s hurting me to know everyone else will get to enjoy a full term pregnancy and the kicks and squirms and be able to take their baby home immediately. I am not sure if this is a sign of postpartum since I feel silly for having feelings like this when other women are struggling to even conceive. Did anybody have any issues similar to this or signs of postpartum like this ?