I bought a Hybrid lilly plant at Walmart last week. It's been less than a week and the blooms that were there have already fallen off and the ones waiting to bloom seem to be dying. What am I doing wrong? Unfortunately the plant didn't come with instructions on how to take care of the plant, so I've been trying to water it when needed. Can someone there give me the specifics on how to save this plant?

Thank you!
Melissa Jones