Thank you, thank you, thank you! I really do appreciate your comments! Great advice and I will start moving things SLOWLY on my bike.
I did have a professional bike fit - twice by a former Olympic racer. Apparently he's the best in our area.
I was a former gymnast in my "younger years" so I imagine that predisposed my back to a weakness, in addition to bodybuilding through college (& beyond). I do stretch and use the foam roller. I should do it daily, but right now it's an honest stretch every other day. I have tight psoas and hyperflexible hamstrings which does lead to a torque in my hips, which changes the pull of my muscles on my sacrum. Thus, muscle imbalance causes my back pain. Yes, it does hurt sometimes when I'm not riding, but totally not to the degree of riding. 60-minutes of climbing the stairs at Harvard Stadium with no pain. 12 miles on my bike and pain starts.
I'm sure the bulging disks are a result of years of combined hard training, not just the biking.
Thank you again SO much for your insight. I appreciate it so much!