I Have 3 Bulging Discs, (L4, L5, S1),spinal Stenosis And

I have 3 bulging discs, (L4, L5, S1),spinal stenosis and sciatica. Lately anytime I bend over and stand back up, like when brushing my teeth or any type of movement such as that, my back crackles. This is just the ladt few days thst it started. What causes that and what is it? Thanks.