my dd who will be 12wks old has been getting more and more fussy with her feeds :(
she was bfed until almost 8wks when i moved her onto formula as althought she was gaining masses of weight she was a fussy bfeeder and it was stressing us both out.
she seemed to settle well onto bottles, only took 2-3oz to begin with and then built that up gradually to 4-5oz and she quite happily settled into her own little routine of going 4 hrs between feeds at day and 6hrs at night, nothing i did, i offered her little and often etc but she was never interested in feeding more often, tho occasionally she would feed after 3 and a half hours without a feed, but tbh she doesnt seem to be a big 'eater'. despite being a big baby, she is on the 91st percentile, for weight, length and head circumference, so a 'perfect' baby for the hv growth charts 
she is not a chubby baby like my others were (she is no 5) more long and slim, but then al my others are also tall and my partner is as well so i think she is the weight she should be, so there really are no concerns over her growth etc.
but her feeding is just getting more upsetting for her :( the trick seems to be to get her happily sucking on a dummy (she uses it occasionaly during the day but sleeps happily at night without it) adn then to take the dummy out and get the bottle in, this doesnt always work tho and she then gets upset.
however other times she will feed better, or else she plays with the bottle and just lets the milk run out of her mouth, but the getting upset is becoming the norm ifyswim?
obviously i need to try and sort this, i dont want her feeds to be an upsetting event for her :(
i snuggle her closely, she gets eye contact and i give and get smiles etc sometimes when tired she settles and feeds better swaddled (she likes to be swaddled for sleep) but other than her being more likely to fuss if she is tired then i cant see a reason/pattern etc in her fussing/refusal to feed.
she is STILL sleeping well despite only taking 2-3 oz sometimes 4oz and happily goes 4 or more hours between feeds, last night she fed between 7:30-8pm and then i woke her at 2:30ish for a feed and then she woke at 8am but wasnt interested in feeding, eventually at 9am she took about 4oz but only by doing the dummy trick, she is now asleep again, she does seem to want to sleep a lot and gets grumpy if she doesnt get her sleep, (bit like me!) but she really is a very chilled out little thing, smiley and content :)
i have a drs app for her at 10:30 just to check she doesnt have sore throat/mouth/ears etc, but she doesnt seem ill.
any advice tips?
someone mentioned reflux to me, but she isnt a sicky baby at all, esp now she is on formula and she sleeps happily lying down, tho when awake she does prefer to be upright but will lie and play under her play gym so i dont think it can be reflux?
oh and she has never really cried for food, only when she is tired, she really is a very content little baby! other than the feeding times :(