It seems like this problem has arisen only 4 days before you wrote to us. There is no history of trauma or accident. With a history of smoking and drinking, I am curious as to how your lower back is functioning (pain, stiffness, etc.). When I read ‘numbness’ I think about a nerve problem (the small two-way electrical wires that run from the brain to the toes). The cramping, numbness, tingling, burning, and shooting pains are those associated with nerve problems. Other times it can be a circulation problem ( diminished blood flow to the feet and legs). If there is deep pain in the calves or the thighs, you may have a blood clot (and therefore should have an exam by your doctor). Other times, the pains will come and go as long as you continue to stretch the affected joints and keep the muscles strong. If the lower back begins to hurt or becomes more painful, then it may be more of a nerve issue. I would give it a few more days and if these feelings slowly resolve, then staying mobile, flexible, and strong is the best advice. If it slowly gets worse over the next 2-3 weeks then it is best to make an appointment with your primary care doctor, for a check-up. I hope this helps.