Newborn gas day 3

My daughter is 3 days old. She is breastfed. The 2 days in the beginning were going fine where suddenly now day 3 she’s being gassy and fussy. She won’t take my left breast which is making me engorged. I don’t know if day 3 engorgement is a thing as I looked it up. My right breast is still somewhat fine but when it gets soft she won’t take it? I don’t know what to do. She doesn’t have her pediatrician appt till tomorrow and before that I have been suggested to not give any gripe water or drops. How can I relieve her pain? I have tried all the burping and she won’t lay flat in her bassinet too. She wants to be held in my arms half of the day. Any suggestions on what I can possibly do? I am a second time mom so I am aware these things can happen. But when she cries, I worry.