Broken coccyx pain is awful, op, I've been there 
If you've not already dosed with painkillers and these aren't otherwise contraindicated for you, can you take both paracetamol and ibuprofen?
You need to space the doses 6 hours apart iirc, doing this, but taken together they make a super painkiller- so much more effective than just paracetamol or just ibuprofen. Should take the edge of your period pain too.
Also, have a cup of tea if taking paracetamol as caffeine helps speed up its absorption.
Obviously don't know your own medical circumstances/history etc and check patient leaflet etc etc but doubling up paracetamol and ibuprofen really helps me when I'm in severe pain.
Then tomorrow, either see if you can get a prescription for something stronger (i used codeine) or look at solpadine from chemist (includes codeine) if youre ok to take it. Codeine also helped me sleep when id broken my coccyx.
A rolled up towel/jacket/jumper/blanket tucked under upper thighs can help relieve the pressure on your coccyx too. When sitting, you can also shape them into a horseshoe shape with the opening at your spine.
Oh and see a woman's physio who specialises in pelvic injury - they'll put together a programme specifically designed to repair the damage and is the only thing that helped me in the long term.
It'll get better, I promise x