So discouraged 😔

I had my son 2 days ago and my milk hasn’t come in yet. So he is constantly wanting to nurse but is not getting full and screams and cries all night/day because he is hungry. I caved this morning and gave him a bottle of ready to feed formula and he gulped it down and has been calm and happy ever since. I really wanted to breastfeed this time around because with my daughter I simply gave up because of the nipple soreness and pain. Idk what to do. Any advice is welcome.