Help heeded with medical badge

Hi, Can you help, Mrs WH's grnadmother passed away and left a number of things from her WW2 exploits. Turns out she was para trained and everything 8O
One of her badges/medals is a enamelled red cross with the words:

Royal Medico Psych Assocn- Certd Nurse-

It is made of silver and has her number engraved on the rear.

Does anyone know where it comes from?

I will try and put up a piccie but I'm no IT expert.
Was she in the First Aid Nursing Yeomanry (FANY)? I think they were para trained, and a bit special to boot. Sneaky beaky and all that. Cool if she was.