yes you can take it down a pot size but how long is it since you repotted it? they take about a month to re-establish and produce all the fine roots they need. try not to over water it as that also produces symptoms of 'unhappiness'.

Hi seaburngirl its been much longer than a month since I repotted it its in taller pot rather than wider which I don't think it likes the leaves some of them have gone drab and edges brown there curling up but some are still ok and look healthy its so confusing its dry now cos I thought I'd over waters it ...the stems look ok there red still ...can I repot to the ordinary compost I use fr all my plants ...thankyou...and its not in bright sunlight or by window ..shall I but off during leaves and stems ...

I have always just used normal compost. Then I'd mist the leaves regularly too.