My grandmother has lung cancer and it's spreading down her arm she's always in pain but is only prescribe tramadol. is this normal?

Depends: Multiple factors considered to determine medication but can't expect to be pain free

Need evaluation: Possible metastasis of her cancer to brachial plexus. Need to know location so direct treatment of area can be accomplished. Tramadol may not be strong enough to handle. It is indeed appropriate to use more potent opioids under these circumstances.