She behaves differently. Happening.

My mom started behaving like a child in 2019 March, I clearly can't describe her. But she acts like a child and she acts scared too, when we ask her the reason she won't tell anything, we thought she was in depression. She works totally fine, cooking cleaning, even when we do all the stuff she'll just sit and do absolutely nothing, won't even use her phone. Now she has started behaving more weirdly, she donates almost everything from our house to others, food, clothes, jewelry etc. When travelling she bows in front of everyone and says namestey from car. She even threw her slippers to the man who was walking bare foot. And the part where I get confused is, when in anger she behaves normally, she fought with me and my brother sometimes when we asked her to stop giving stuff to random people and stop inviting everyone walking outside to our house and ask them water coz it's corona time. She behaves like she is totally fine when she is angry. Please help me understand what's happening.