Are you sleeping enough?
Fitness
Would like to add, are you also eating enough?
I mean I get about 6-7hrs daily. My work schedule makes things hard, and then with overtime being unpredictable it's hard
That's understandable. DOMs from training legs definitely kicked my ass when starting out, but I gradually acclimated.
How many sessions have lead to 5+ days of this for you so far?
The first leg I've done in 7 years was friday. Before that I was just running 4 days a week(easy run, tempo, interval, and long run). I have huge legs but trying these different compound movements makes me realize how weak I am
I've found that the best way to get through it is to move through that range of motion more often, unloaded. Stretch, do a handful of air squats, then do them again later, then again later. Not saying you have to work out, but moving thorough it and exposure will help.
Edit: also drinking lots of water will help.