emma - as i understand it babies have "growth spurts" at around 6wks and 14wks and 6mnoths (i beleive) when i breast fed my dd would have days when she would feed and feed and feed and nothing would settle her. unfortunatly there is nothing you can do about it. but it does get easier. and as they get older it gets easier!
just incase you are unsure of the signs of colic/wind incase it is that, babies will pull there legs up to there chest, will be unsettled and often have a blue tinge above there top lip. infacol is a fab product for this. and baby massage is also great. lie your baby on its back and rub (in a clockwork motion) your babies belly. it is so rfelaxing for baby, mum and i found helps them sleep.
hope you get a good sleep soon. if it does continue ask you h/v. get them weighed and that will be able to give you an indecation of weather they are having a spurt. good luck honey and sorry if i have told you what you already know!! xxx