Actually, I started working when I was 18. I’m going to be 80 this year. Employers got away with pretty much whatever they wanted then. Things are much different now.
You started work about 61 years ago and there is no reason to think you were being underpaid at that job.
“In 1963, the Equal Pay Act enshrined into law equal pay for equal work, explicitly prohibiting pay discrimination on the basis of sex.”