almost there

So when I went to my dr I was 34 weeks and he said that if I go into labor at any point they won't stop it. My back has been hurting no matter what I do and I have had constant pressure on my pelvic area. I decided to take a shower to relax and my whole stomach felt like it dropped like when you go down the giant hill on a roller coaster so I didn't know if any other moms had experienced this feeling or what? I was induced with my last two so I never had this and my first son I was in complete denial about my water springing a leak and thought I was just peeing myself...