I've been there. It feels really bad but usually it settles quickly enough for me. You do have to be careful with the squats though. I found warming up an ice pack style thing to be really helpful to loosen it out.
Keep plugging away and you will get there.
Thankfully it settled fast. nearly good as new today and wasnt too bad yesterday. Got a really cool themracare heat rap from the pharmacy as well is ibuprofen
Yoga should help with recovery and strengthening your back again :)