Hang in there, the last stages of pregnancy bring on so many thoughts, ideas, uncertainties. I have been up literally for hours now trying to get back to sleep with no luck. Nightmares too when you are pregnant can be so intense because of your hormones. I usually get very intense ones at the first trimester. Best thing to do is what you are doing, posting to other pregnant women so you know you are not going crazy :D
So normal and sorry to say those weird feelings stick around for a couple weeks after the baby is born, but then you should go back to being yourself again. End of pregnancy comes with all new hormonal surges that prepare you to be a mom and take care of that little one. I got scared walking around my house the other night to get a drink of water. It's silly, but does get better.