I can imagine it was nasty, though I think it was really what she needed to really get rid of problem!
For my DD the surgeon was so going for it I was thinking he's going to damage the nerves or the blood vessels, It really was awful!
DD had a little suckle straight after, my boob was covered in blood...
yes, yes, do wake her, and if she's sleepy change her nappy, strip her off, skin to skin so she 'll be more alert!
if she slips off or you still have pain break latch and re-attach her.
keep going, she needs to practice/re-learn! and you could even bf every 2 hrs in the day as she also needs to stimulate breast big time to increase milk supply!
extra feeds for 3-4 days usually does the trick, then you can then relax a bit and get her back to a good routine.
also I'm sure you'd do it anyway, but check her weight gain once a week, she should start putting on min 20g/day.
that and wet nappies and yellow poo will reassure you that things are improving and also the feeding will be less painful.
well done you, brave mummy! very proud of you!