It sounds like you're trying to design a device that's intended summon aid when a patient, who's otherwise incapable of taking action for self-preservation, cries out. Based on what you've said about the patient, that outcry might be in response to something interesting, like maybe that the curtains ablaze, or it may be based on nothing in particular that an attendant could see.
What are the consequences if the device fails to detect an outcry? Could the patient suffer serious injury or death? If so, then devices manufactured for the hobby market would be inappropriate for this application, as would an inexperienced designer. If the consequences of failure could be dire, I'd recommend that you give up this effort immediately, and leave it to others who are skilled in the art, can test the device extensively, and get it listed for its purpose.
You don't say whether this project is intended for a specific patient, or whether it's intended to be generally applicable for any patient. Given the range of frequencies for human voices, and the range of effects of dementia on vocalization, coming up with a general device will be a lot harder.
You ask about distinguishing an outcry from other loud sounds in the room. I'd be surprised if a dementia patient's room has so many other loud sounds that it's necessary to make the distinction. I'd expect, for example, that an attendant would want to check the room if there were a loud sound, to determine that the noise wasn't the patient's body hitting the floor after he fell out of bed. If excessive loud sounds are a problem for this project, I'd think that you'd want to do something about the noise in the room before you'd undertake this project.
Finally, I'm not seeing any evidence that you've made any progress at all in this project. No code, no schematic, and the photographs are advertising shots.
Is this an academic assignment?