How tight are your hamstrings? If they and your calves are very tight, they will pull on your lower back and cause issues as well. You may not be able to stretch them by yourself.
Lay on the bed. Lift your leg. Have your wife place your hamstring on her shoulder. She'll likely need to straddle your other leg. Straighten your leg. Point your toes down toward you (you should feel a deep stretch in your calf at this point). Rotate your foot. slowly. All while she slowly pushes your leg against your leg to the point where it feels tight in the hamstring. Then stop and keep pressure there for a 20 count.
Do this 3-4 times a week, trying to get a deeper stretch each time.
Does that make sense?
Complication makes it easy to explain failure.