The symptoms are typical of impingement of the sciatic nerve.
There are many posts and places on the internet to review options.
An MRI of the lumbar region (L1-L5) is the first step.
Then you should get a referral to a rehabilitation specialist who will demonstrate several exercises and watch as you show you have learned them.
You have to be careful when lifting (use the knees and keep the spine vertical) and avoid all heavy lifting in the future.
A TENS device is helpful in relieving pain. It works in a way similar to accupuncture.
A surgical procedure called a laminectomy is an end-of-the-line option. A segment of the disc will be removed, provide more space for the nerve.