Tight-Hypertonic hip flexors and abdominal tightness/pain?

Been dealing with this for a while. I went from a very active job to sitting all day a few years ago. Very active male, fit and no health issues. The stomach muscle type pain has been intensified since sitting. Is it glute weakness and overly tight quads and lower back? My lower back never hurts, that’s the first thing people ask me. It’s just the abdominal referring type pain.

Just seeing if anyone understands this or ever dwelt with it.

Had CT Scan months ago to rule out scary stuff.

Any suggestions would be awesome. 😎