1 week ago I fall on my butt And today in gym I had a pain in the lower part of back The pain is shallow and not sustained Is that lumbago? Wht ttt

Lumbago. is a very general term used to describe low back pain. It can be mild or severe, acute or chronic. It does not indicate a specific cause or back pain condition. While you can't know for sure, in my opinion it is more likely than not that your fall of a week ago has contributed to your low back pain. Avoid aggravators including lifting, use ice or heat, stretch, carefully exercise. Should improve.