This is true about nurses and I fully support them in wanting a fairer increase. Nurses are however paid for overtime and they don't fund the running of their wards out of their own pockets....
I work beside teachers, I used to be a nurse and my husband is a senior nurse. I can certainly tell you that the experienced, more senior nurses are not paid for their overtime but are expected to get the job done anyway. DH's wage is running about 20% behind where it should be and he puts in extra hours every week, even during his 6 weeks of annual leave. I imagine many senior nurses do this regularly.
As I said in my previous post, nurses can't strike where the teachers can and that gives you an advantage, but don't go believing that you are the most exploited group.