Wife has severe cramps in lower abdomen and minor light colored dishcarge that has an odor. Seeing gyno tomorrow. Worried. Bv? Cervical cancer? Cyst?

Stay positive. Several things could cause these symptoms. Your wife is doing the right thing in seeing her ob/gyn, as diagnosing the cause of her symptoms will require an examination and likely some lab tests. If she has tolerated Ibuprofen before, she could consider Ibuprofen to help with the cramping.
Infection likely. With pain and odorous discharge, most likely will be an infection which should be able to be treated with antibiotics.