Muscle strain or herniated disc

It happened this morning while doing my regular light exercise like squats, lunges, laid-down cycling, planks, situps, and crunches. So I was just doing my squats (no weights), and when I got back up, I got this intense stabbing pain at the base of my spine, a little above the tailbone. I had to hold onto the table and stay still until it stopped hurting.

Then, it wasn’t so bad, and I could move around carefully. So I went to work. But it gradually got worse with the travel and movement. Now I’m back home, and I can barely move. I have to hold onto the walls to walk.

Certain movements give a ‘popping’ that I can hear and feel at the spine with sharp and stabbing, debilitating pain. I cannot sit on my butt, I cannot stand straight or walk with pressure on my heels, have to tiptoe putting my weight on my arms against the wall. I cannot lay flat on my back, even with my knees bent.

Basically can only lay on my side with a pillow between my knees-bent slightly, and I still feel a dull ache. The ache goes all through my thighs and somewhere in my calves but I’m assuming that could be because of the weird walk I’ve been doing.

So does this sound like a muscle strain I should stretch out with like cat cow like exercises or something more serious like a herniated disc?