Just remember that the few hours after heavy exercise are the most dangerous. Many people, runners, lifters, footballers etc all learn perfect technique and use of strength to keep the core tight. It is 30 minutes or sometimes longer after exercise that the most injuries occur, and this is because when their muscles are in a fatigued state they let them relax, and subsequently uptake bad posture. The fatigue causes a lack of muscular tone, and their body distorts in an abnormal way, causing injury long after the exercise.
This leads many athletes to blame the exercise they last did in their training, when really they have suffered no acute trauma at all! This is a bad self-assessment, and all they need to do is concentrate on upholding good posture (natural lordosis, curvature of the back with a 'high' chest, and keeping core a 'muscle tone' to uphold the spine) for the next few hours after exercise.
Pinching a disk can cause a flare up in the glutes and surrounding muscles because of the sciatic nerve runnning so closely trough them. This can cause tightening of those muscles, so just work on your hip mobility (regaining the ability to drive your knees outward when squatting), and keep your back in a natural lordosis the whole time.
Have a look through this, though you might be a bit more advanced than the exercises suggested it is still good to learn about your own injuries.