Lower Back Pain: How to Tell Good Pain from Bad Pain? Solution?

Good pain, bad pain. How to tell the difference? I’m pretty sure I over did my squats last session which was about 4 days ago. I knew the day of, I worked it hard. Lower back has been sore since. Been doing ice, checked with reg doc, prescribed muscle relaxer. I don’t have restricted movement, but it is as sore as it’s ever been. I’ve thrown my back out plenty of times to know what that feels like, this isn’t that. It’s just sore. When can I go back to squats? I did overhead press last night, no issues, followed up with about a 2 mile run, no issues. I’d hate to give my squats up for awhile, but would like to know what you good people have to say. Don’t want to injure myself, this is all pretty new to me, going to the gym, doing weights, and possibly overdoing something. Stretches? Must be a thousand stretches out there, thanks, Dave