If you're gonna start lifting again, don't do anything that puts pressure on the back. Avoid things like rows for example, squats and even standing BB curls. It's not that hard to find alternatives that can work the back without hitting the lower back.
In other words be conservative, let more time go by during which the back isn't involved or aggrevated. And continue to do more daily stretching, jacuzzi, etc.
If you're lucky and it's not serious you'll be able to work thru the remaining pain, if it's something more serious you'll notice that the pain never quite goes away in which case it would eventually be time to see a doc.
And of course backtrack to the likely cause of the injury and don't repeat the problem causing activity in future.
