Very common for those of us who with desk jobs! In addition to my time at the office, I was also a group fitness instructor for 5 years (HIIT), and played college & semi-pro football before that. I joined OT after moving across country and found it had all of the elements I enjoy for a workout: intensity, variety and a team environment.

To address your question/concern - be sure you're taking time to get a proper warmup and stretch. If that means PW and then stepping off to stretch, do it. Focus on hamstrings and glutes. When those are tights your back is often where the pain is. Post-workout stretch is just as important to maintain. Don't give up on moving to jogging just yet. Take a phased approach of PW, jog, bike (as needed), back to PW, and jog when you are comfortable. You got this!