What's your question? Ask

Congratulations! You have seeds! Yes, this is perfectly normal. Here's an article to help you grow those seeds, if you want to: https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/calla-lily-seed-info.htm

This article discusses several aspects of this problem: https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/drooping-calla-lilies.htm

Yes, calla lilies frequently form seed pods, which can be used to start new plants. https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/calla-lily-seed-info.htm

There are literally hundreds of varieties of calla lily, that bloom from spring through fall, in a range of climates. The kind you're using may not be ideally suited for your climate. You can check with the count extension service for the names of varieties you might want to try. This link will help you locate one. https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm
These articles might also give you some more basic information:
https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/growing-calla-lilies-and-care-of-calla-lilies.htm
https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/make-calla-lily-bloom.htm

This is the seedpod, which should be left to ripen on the plant before collecting for seed propagation. If it's already yellow and feels soft, then it should be ripe enough to use. Take out the seeds and allow them to dry out some (Note: they may require rinsing with water to remove pulp). They can then be stored after drying or planted right away. Keep in mind that they take longer to mature when planted this way verses offsets. Here is more info: https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/calla-lily-seed-info.htm

Generally, it is recommended that you discard any broken or damaged bulbs. That being said, I think if you dust them with an anti-fungal powder prior to storage, they should be ok (if not, it's no worse than tossing them now, so why not try). Make sure the bulbs are dry, however, or rot will set in.