As a mum of 3 who had reflux I have some advice.
To establish if it is proper reflux and not just a sicky baby.
Does she fuss at the breast? Does she seem to pull off and squirm and look uncomfortable, off and on, off and on. If yes and if it gets worse it is definitely reflux and she will need Omeprazole.
Gaviscon doesn't work with breast fed babies and Omeprazole is the more expensive drug (and most effective).
Not all reflux babies loose weight, in fact my middle child fed and fed and fed and looked like a mini sumo in weeks of birth after only weighing 6lbs.
Sometimes they use it to comfort the pain as breast milk has a natural gaviscon effect albeit temporary!
It then comes back up with a whole load of stomach acid and off the cycle goes again.
DO NOT RE FEED AFTER SHE IS SICK. She needs at least 2 hours from one feed to the next and not sticking to this will only exasperate the problem. If any breast feeding natzi's jump in with 'babies should be fed on demand' then this was advice from many a pediatrician who dealt regularly with reflux. Even a baby without reflux should not be fed one feed on top of another as the digestion system is way to immature and needs the time to digest the last feed.
I bet when you make sure this happens the problem will disappear. There is every chance she doesn't have reflux (GERD) and is just being fed too often.
I know she will seem to want this soothing feed routine but she hasn't worked out the fact that it is causing her discomfort.
I had to walk the floor from feed to feed with my refluxers. It was hard, hard work but it doesn't last long and you will see her calm down once the feeds are spaced.
I hope she doesn't have it but if she does, you know the signs and you now know not to be palmed off with gaviscon!
Raise the moses basket quite significantly, 4/5 books each leg. Once she is 4 weeks you can sleep her on her tummy, she will be able to lift and turn her had no problem. I did this with my last two - as long as you don't smoke? 95% of cot deaths are to smokers.
Sleep with her on your tummy just now if you can. I got rid of my husband, the pillows and wore a light fleece and the duvet just over my legs. I positioned myself right in the middle of the bed. She will be a hot water bottle and you will sleep very still and soundly if you are tired enough, im sure you are! She will sleep longer and happier like this and you can try the basket again in a few weeks.
Don't lie her in a flat pram. Keep her in a carrier if you can for now.
It will all pass soon enough. Don't over worry about what you should and shouldn't do. Do what keeps her happier and you saner!
Congratulations though, id have a forth - even with reflux!!