becs,
Your postings take me back 7 months to the 'dark days' with my ds. Dreadful silent refluxer and ended up in hospital. Dropped down to 2nd centile from 50th, constant screaming day and night and really difficult to feed. It was difficult to watch ds in such pain, and I felt helpless as a mother.
Do continue BFing. I started giving bottles because feeding was such a battle (before treatment this is) and it made the reflux MUCH worse (although he did gain a bit of weight). Smaller, frequent feeds were much kinder on his tummy.
We saw a big change with the gaviscon although it bunged him up badly! I gave it mixed with EBM or formula in a 5ml syringe before each feed. He also had ranitidine as well.
Thankfully, after a couple of weeks of treatment he stopped crying, started sleeping and feeding and became a much happier baby. He is still a little small for his age now but a delightful child. You would never guess that he had been through so much pain in the first few months.
It WILL get better. It is really hard in the beginning and I remember feeling defeated and jealous of other mums with their placid, contented bundles.
After each feed, make sure ds sits upright for at least 30 mins (bouncy chair/being cuddled). We also found that putting him to sleep on his left side made a big difference to his comfort at night. Raise the head of the bed by 4" or so (we put tins under 2 legs of the cot).
If it doesn't improve after a couple of weeks, then go back to HV or GP and press for some extra help- there's loads of things that can be tried.
Good luck.