I have been experiencing extreme stomach pain I was recently diagnose with gastroparesis. What can I take for the pain?

See a GI. Gastroparesis can be helped with some meds such as metoclopramid or Reglan (metoclopramide) although it is not specifically for this problem and may have its own side-effects . There is a electrcial stimulator which directly stimulates the stomach's emptying which can be effective. This does require a surgical procedure and the stimulator itself is quite expensive.
Avoid narcotics. If your stomach pain is indeed related to gastroparesis then the last thing you need is ti slow down your bowel function further. All narcotics can worsen gastroparesis and slow down your gut more. Your doc may want to try baclofen, a smooth and skeletal muscle relaxant, to see if any of your pains are from colonic spasms.