All the advice is right on the nose. Five eggs is not that much for an ekkie but her getting thinner and the inability to perch is a serious concern so you need to take her to a vet asap. In the meantime, you need to let her sit on the eggs instead of taking them away (fake eggs are the best option, IMPO) You need to eliminate her access to dark places. You need to stop caressing her. And you need to reduce her protein intake drastically. Female ekkies would usually not lay without a male in attendance (in the wild, they usually have two males each to feed them while incubating) so in order for your bird to have started laying in February you must be feeding way too much protein, exciting her with your caresses and keeping her up long after the sun sets.
As to reducing the number of hours of light, yes, it is true that birds produce sexual hormones when the days are long but shortening the day doesn't always work because of the relationship between twilight and the setting of the point of refractoriness (internal breeding clock). Studies have confirmed that birds can go into breeding condition even with very short days so, sometimes, just putting them to bed early doesn't do it.