It's a tropical hibiscus, Latin name Hibiscus rosa-sinensis. It may not be a particular cultivar.
I wouldn't use the super phosphate on hibiscus--they don't like a lot of phosphorus so it can actually hurt blooming instead of helping. Any fertilizer that has nitrogen & potassium but not a lot of phosphorus will be fine. The dung probably has mostly nitrogen so it should be OK.
I don't see anything wrong with your plant--different cultivars can have different size leaves so I wouldn't worry about the leaves being smaller. As far as the flowers, tropical hibiscus flowers don't stay open for a long period of time. If you are having cool weather they can sometimes stay open for a few days, but in hot weather mine typically just bloom for a day. They also can be a bit reluctant to form seeds--I grow a ton of tropical hibiscus all in close proximity to each other and I think in 6 yrs I've gotten 2 seed pods, and neither produced viable seed. Some of the fancier cultivars just don't set viable seed--yours looks more like a garden variety one so maybe it can set seed, but you may need to help it out and hand pollinate if you want to give it a better chance.