Strange Feeling in Lower Back w/ Squats

Ok i will start with a bit of background:

I’m doing HPmass for the second time (although my first time i had to stop at end of week 3 because i broke a finger)
today’s session was the last legs day of week 2
I’d taken the last 2 days off which is very unusual for me when on hpmass

so from about set number 2 everything felt very heavy today, perhaps because i’d had a very long and tiring weekend. im now on set number 5 and on the 3rd rep everything is going fine and when i hit the bottom of the squat as i am just about to come back up i have a VERY strange feeling in my lower spine (coccyx area)

i manage to get out of the hole and re-rack the weight but all the way im feeling this very strange feeling which is bordering on painful. i walk away to the water fountain and the feeling is still there but a lot less. i wait until the feeling is gone and for some reason decided i want to see if the feeling comes back if i un-rack the weight again thinking it may have just been a cramp or something. i walk it out but the feeling comes back straight away. i re-rack and go home as its really shook me up. my lower back now feels like its had a bit of a workout but the feeling is mostly gone now

ive had lower back problems before (pain around lumbar if in one position for long enough …due to being fat and lazy + pretty sure i broke my coccyx before) but both these were a good 5 years ago and since working out all back problems have been sorted but never had anything like this

wondering if anyone has had anything similar or knows what it may be?

Sounds like one of the discs in your spine didn’t like what you were doing. You probably just tweaked it a little bit - if you would have torn it (slipped or herniated are synonyms for this), you would have known it.