Bedtime muscle cramps and spasms. Only at night. Severe. Being put on a low dose of diazepam. I think carisoprodol but my docs a shrink. Advice?

Magnesium. Sometimes nocturnal leg cramps are due to magnesium deficiency. Occasionally they'll be caused by very tight calf muscles which need to be stretched before getting into bed. Try taking some magnesium to see if your cramping improves. Your pharmacist can instruct you on the type and dosage unless you discuss this with your physician.
There are better. muscle relaxers than Valium or Carisoprodol which are essentially benzodiazepines and addictive. Fkexeril, Robaxin (methocarbamol) or Baclofen are better choices.