lower back causing lower abdomen pain

My lower back has been hurting for about a week and a half I can put my finger on the place on my lower spine and feel it. I have a pain that wraps around the front to my lower abdomen almost directly in line with the lower back pain, I went to my doctor and had a ton of tests that showed nothing and just got an antibiotic that I’m taking that wrecks my stomach. My question is are there nerves that wrap around the body that when you have lower back pain like this that could cause lower abdominal pain in relation to the back.
Thanks for any advice.