pressure and pain

I have been having so much lower back pain and pressure around my hips. This is my second baby, but I don't remember being this misirable. I have being feeling like I just did a three hour work out and sore.  Saturday it was so bad I had to stay home from my best friends engagement party because I was feeling so much back pain and pressure I didn't want to get off the couch. A certain way I sat took the pain and pressure off.  I have sciatic nerve issues in the past and with my last pregnancy had to go to hospital at like 32 weeks because I thought I was in labor the pain was so bad in my back. But she said it was the way he was laying on my nerve.  I'm due march 18 and I honestly feel like he is going to come early with all this pressure and pain I have been having and only being 25 weeks. Anyone else going through this ???