degrading picture quality with camera iphone 5

When I first got my iPhone 5 about 10 months ago, it made rather nice photos... decently sharp, at least if the lighting was optimal. I look back at some of the photos I took the first day or two and marvel. I have a picture of a bee on a tiny flower that clearly shows the bee's fur and flower's eensy weensie stamens.

Now, usually the photos are blurry and low res, even in good lighting.The camera cannot focus on a small flower close-up even in the best lighting.

I have HDR on. The file sizes usually come in well under 1 mg. Even if it uses higher megapixels (2-3 is the highest I see), the picture quality is rather sucky. The lense looks clean.

The way it handles light and shadows is pretty deplorable, but that's never been good ...any workarounds known?

The people in the Apple Store said there is no way to override the presets and force the camera to take higher resolution pictures than it thinks it should. They did not know why it takes such small size pictures. And, they had no comment about the change in the focus capability after looking at my photos.

Any ideas on why my picture quality has degraded?

Any ideas on how to fix it?

Input much appreciated (even if only commiseration).

Thanks, Teelbee