I could not find an answer for my question despite researching about the subject.

What does sadness feel like? I have read that people feel it in the heart too. Do they literally feel something in the heart? What are the other feelings people feel when they get sad. I understand that it is a negative feeling such as anger but I am sure that it is distinctly different than anger and people could differentiate between the two feelings. Are their specific symptoms of feeling sad mentally.

My second question is what is the difference between sadness and depression? Is depression similar to sadness but just stays for a longer period of time?