Frustrated and tired

Jennifer
My baby is 2 wks old and sucks at nursing. I don't get it! I breastfed my oldest child for 15 months and we got off to a rocky start but we did it. She wanted to nurse every 30 minutes since day 1. As soon as my milk came in, it got easier.  With this child, however he can barely latch. After he lost a pound during his first week, I was told to use formula.  I cried and cried and tried the nipple shield which helped a lot.  I'm trying to get off the shield because it's gross and getting worn out. But he latches and spits it out over and over. It's so painful and annoying.  I just want to give up, but I really don't want to use gross formula!!!!  It takes us 20-30 minutes to start a feeding and by the he's exhausted and I'm so frustrated I resent him. I'm tired and just want to have a good breastfeeding relationship with this kid.