Geranium Problems

Hello Everyone : I had a lovely geranium this summer which was bought from a little nursery. It did well most of the summer, I repotted it, fed it and took good care and it lived in a sunny spot which go the sun from the east. I was told it's best to bring it indoors for winter and ever since it's leaves are curling downwards and going brown then dropping off. The actual stem of the plant looks alright and it keeps shooting new leafs from where the dead ones were but as soon as they get a little big they start dying off as well. Here is an image of how it was oringally and how it is now ... any suggestions welcome! I do give it plant food and it's sitting on top of a shelf that still gets quite good natural light (all the other plants on the shelf seem fine...)
I've read it could be aphids or a lack of some kind of ingredient but not sure what it is most likely to be...
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Don't feed it at this time of year - it needs to slow down as the weather gets cooler and daylight hours get shorter - also keep it almost dry. Pelargoniums (not called geranium nowadays, they're something different) need hardly any water in the winter.
Take off the poorly leaves and put it in as sunny a spot as you can find and don't water it for ages and ages.
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Poor thing doesn't look at all well. Pelargoniums react badly to being moved so yours may well be complaining about coming indoors for winter. Follow the advice to cut down on the watering and keep an eye out for fungus gnats that can be a problem in compost and will leave you with a plague of tiny, black flies. They tend to be more prevalent in peat type composts.
Pelargoniums can get viruses, just like the rest of us, and if yours doesn't perk up in spring and continues to have distorted leaves then bin it, and not in the compost bin.