Is this discrimination due to being pregnant

Charley

I've worked 16 hours minimum the last year or so, I'm not contracted to that but have always been given no less than that and always offered overtime. suddenly my hours drop to 15.5 and no over time, pushing me to around £114 a week. I confronted my boss about this earlier now she's back off holiday and was finally given a straight answer, it's because they can't afford/don't want to pay me smp, the threshold being £116 on average a week so the treasurer and secutary of the club cut my hours to push me under, no one has told me this is why until today, everyone has received cuts but no one else refused overtime. Do I have a leg to stand on that they're discriminating against me because of my pregnancy?