New mommy

Br
Not sure how I feel about all of this hard work..mostly the breast feeding is what is killing me..I don't know if I should pump and feed her the bottle (about 3 oz total) or if I should let her feed out of the boob (maybe and oz in a half outta one side)..she normally eats from one side of I breast feed but then my other side stays full and if I pump I feel like it's not enough to freeze/save and it'll just go to waste..
Oh and she now has an issue with spitting up..and I'm not talking about a little spit up..I mean full on projectile everything out as soon as you burp her..the doctor said to remove dairy from my diet which i did but nothing has changed..I feel like she pukes up everything she eats and then goes hungry because I am empty from her feeding...not sure what to do at this point..she is 3 weeks old and her appointment isn't until next Friday.. 😫