Thanks for all the replies everyone. I was reading but kinda had my hands full ;-) Touch wood, she doesn't seem to have reflux - at least not yet. Both DDs 1 and 2 did, so I'm crossing everything we're (and most of all DD3) are going to be lucky this time

Ended up putting her back in the ergo and doing the vacuuming (just as well the neighbours can't see/hear us or they would have thought I was nuts doing that at 11pm!). Needed to do something for myself to take my focus off the screaming, and hey the floors can always benefit! Not sure if it was complete exhaustion or the noise but she finally fell asleep and then slept until 4am. Seems to be back to her normal, more contented self today so hoping she stays that way.