Worried - bad lower back pain!

Hi guys. My first post eek! I had my positive tests on Saturday (struggling to get Drs appointment tho to kick start everything). But I'm really struggling with lower back pain. I've got home from work (teacher) and have had to sit with a hot water bottle as I'm so sore. I think I can only be about 4 weeks 2 days ..... Is this pain normal? Only other symptom is bloating and I had a urine infection last weds which eased on Saturday. 
Thanks xx