A bless ya hun don't worry I spent many a night crying with pain when feeding mine to start with, they never say how much it can hurt. Don't know how the Tongue tie will affect it obviously, but I'm sure it will get easier, you both probably just need to learn how to do it properly with each other, he'll get the hang the hang of what works best for him. I loved breastfeeding, but stopped at 6 month when her teeth came through
Have you thought about maybe doing one formula feed a day, or maybe at night to rest yourself, I did this with mine as I had depression and found it easier to cope of Missed a feed out, and lily had no problem switching between the two, she was an enthusiastic sucker too xx