Reflux or just sicky baby?

[KJM2013]

LG is 12 weeks on Tuesday, this last week she has become more sicky than usual but nothing has changed. She's bottle fed HIPP organic with Dr Brown's bottles have 5/6 feeds a day taking on average 4oz, I make a 5oz bottle.
She happily takes bottle, shows no sign of discomfort and has always been a good burper so we've been lucky to escape colic (my first dd screamed like a banshee with wind, so been there and got the t-shirt).
However, after a possible bit of posset with a burp she now is sick after a feed (just milk, nothing sinister) but more than just a posset. She can do this 2 or 3 times in the next couple of hours, particularly if moved or sat up after a nappy change but sometimes while she has been sat up a while.
Again none of this seems to bother her but wondering whether the increase in volume of sick across this period, is something to worry about?
I thought reflux would be giving her more discomfort if it was that, she just seems to be sick a fair bit and this has only started in the last few days, so seems late to start reflux now.
As it's only been a few days, it would be hard to say she'd started losing weight if I take her to the clinic, I guess.
Thoughts?

I've found that DS (14 weeks) has days where he's much more sicky and days when he's fine; normally the former is when he's eaten a bit too quickly but sometimes it's just quite random. It doesn't seem to bother him at all (unless it comes out his nose which he hates) and has plenty of wet nappies and is gaining weight so I'm trying not to worry too much.

That is odd, my immediate thought was pyloric stenosis, but she is maybe a bit too old for that, might be worth thinking about. Keep an eye she doesn’t become dehydrated and could just be a bit of gastroenteritis.