Wanted to know a bit about Lower berth/Sr citizen quota. Has anyone travelled?

IRCTC shows, for women, Quota starts from the age of 45.

And my mom (aged 47) would be going by quota for the first time, she is afraid that it might not be valid. Like how is it so low for women (45), it could be 55 or something. Her relatives also told her this.

She is afraid that she might have to pay fine.

So, has anyone or their women relative (of similar age) has travelled by that quota? I want to confirm.