I bent down now iv a sore back even sore wen i walk and put my left foot to the ground what is this ?

Strain: Acute onset of low back pson agter bending over number ine DX is muscular strain with or without spasm normal course is 6 weeks of improving pain to 80% better with reoccurences with similar activities many therapies sbsilable but time is the primary and consistant healer. Seek doctor neurolgic symptoms develop like leg pain numbness tingling or weakness.