DD does this and its only got worse (she's 9months now) I usually give her something to hold (muslin rattle ect) if not she whacks the bottle or pulls my hair! She doesn't arch her back though? Maybe try feeding in a slightly different position?
Ds does this but he's breastfed. He punches/ grabs my boob while he's feeding and if the milks not coming quick enough he will arch his back (seems like frustration) until my milk flows a little faster and then he settles. I'd maybe do as others have said and maybe use a larger flow teat and see if that helps. Unfortunately my boobs don't have a larger flow teat do looks like I'm stuck with sore boobs for now lol