Once I have paid back my maternity pay I will go and find another role where I am respected for my skills, not judged for being a mum

I taught at my school for 7 years. I had worked my way up to a position on the senior leadership team, coordinating English and was being paid a TLR (approx 3000 per annum) when I left at 37 weeks pregnant to have my baby.
I returned to work after 10 month’s leave, reducing my hours to part time. My headteacher seemed to feel he was doing me a favour by allowing me to work part time, then refused to consider having a part time English coordinator (he’d actually already given away the role to another member of staff in my absence) and so I lost my place on the SLT, my leadership status and with it my TLR.
I know this is not as bad as some of the other women on here who have lost their jobs as I still have a job and am (sort of) able to carry on with the career I love. I did however seek advice from my Union who told me I had been discriminated against and had a case, they asked if I’d like a representative to come and speak to me. But to be honest, the way my Head teacher has treated me I daren’t kick up any fuss as I don’t want to make work any more unbearable than it is!
Such a shame how many workplaces seem to assume the same; a woman returning to work having had a baby is somehow less of a worker, or less fit to contribute meaningfully to the workplace. It’s just not the case! Once I’ve paid back my maternity I am hoping to move on and restart my career which I feel like has gone about 10 steps back since I left to have my baby.