I need to clarify a few statements here.
The generic name for Progynova is estradiol valerate. This is a pro-drug to estradiol. It is not active in the body until the valerate portion is cleaved off and releases active estradiol. It is considered to be bio-identical, but not until the valerate portion is gone.
This medication is usually given by intramuscular injection, with 100% bio-availability. Since the valerate portion is not removed all at once, it acts like a timed release medication, with a half-life of 4 to 5 days. The oral form of this drug is only 3 to 5 % bio-available and has a half-life of 12 to 20 hours. Because of the limited bio-availability, very few people, in the US, take oral estradiol valerate, preferring to take micronized estradiol, either oral or sublingual.
From the original post, she reported two unpleasant side effects. The dizziness and leg cramps are not normal side effects associated with estradiol valerate. Dizziness is associated with other hormonal disturbances, such as in menopause. The leg cramps would most likely be caused by something else.
While we try to be helpful and supportive here at Susan's Place, we cannot diagnosis your specific situation. We can point you in the right direction. As others have said, you need to have a talk with the doctor who prescribed you the Progynova. There are other choices for HRT.