No no no, it's fine - it can be soooo hard with your first. It's awful when they really cry. I'd say she still has some wind that is getting through even after she has burped. When it works its way to the gut/bowel it can be really uncomfortable - hence arching back. She wants to suck to soothe the pain, but it can get into a viscious circle of more feed on top of the burps yanno?

Have you got a sling? Try that, if you can let her sleep on you - her tummy will be more comfortable as well.

Of course it's not the wrong thing to hold her - and if anyone tells you comforting a yelling bubs is spoiling them, I'll be over there chasing them away with a broom.

Oh btw, I'm not sure how old she is, but babies are notorious for 'waking up' around 1-2 weeks after birth.