TBH LL, I think is one of those 'instinct' things, the temp of 37 is pretty normal, the higher 38.5 is only really bordering on a 'high temp.' and if calpol is controlling it, I wouldn't worry too much about it.
What has she eaten today? Is she still drinking? The screaming might not have been pain, more worry, it is scary when you're sick, and I don't know anyone who enjoys it!
Though I have kind of played all this down a bit, like I said these things are about instinct, and I can't see her obviously, (and am no doctor either, only know about the temp. stuff because DS2 get's febrile convulsions).
I would say as long as she still takes fluids, I'd leave her for now, unless obviously anything drastic happens.
Poor little thing, she's not had a good run of it recently, has she? - Or you! Hope it is just a 24 hour thing