Firstly, massive congratulations on the birth of your baby! Wishing you a speedy recovery.
I don't have any experience of tongue tie, but I did breastfeed DS until he was almost 3 and a half, so I can offer some insights on the breastfeeding side of things...
Are you still attempting to breastfeed at the moment, or are you formula feeding until the tongue tie has been resolved? If the latter, I would say that even if your milk hasn't yet come in, pumping (whether by machine or hand) might be a good idea to encourage production - assuming no complications, your supply will be driven by demand (I.e., baby feeding / attempting to feed). If baby isn't currently feeding, it's a good idea to ensure that your breastfeed are being stimulated and encouraged to produce to prevent the drying up issue you experienced previously.
As for pain, I know they say breastfeeding shouldn't be a painful experience, but it often is, if you don't have access to a lactation consultant who can help you establish a correct latch. As far as I'm aware, we didn't have any latch issues, per se, but I can tell you now, it was still bloody painful for a good couple of weeks or so. I had blood blisters on my nipples, and the initial latch was pretty excruciating at the beginning of every feed, however, your nipples do eventually toughen up and desensitise to it, so it might just be a case of persevering through it (unless it is making you downright miserable and you are struggling). I personally just used lansinoh, but I have seen some people using the old cabbage leaf method - not sure exactly what's in cabbage leaves, but some sort of compound that supposedly helps with pain relief.
Finally, just wanted to say that feeling overwhelmed is very, very normal - for "the most natural thing in the world", it really doesn't actually come naturally. But, if you can eventually establish breastfeeding, it can be a lovely experience. Well done for giving it a go - in the end, though, just make sure that you do whatever feels right for you.
Wishing you all the best, whichever path you take 💖