Hi there,
Unfortunatly you probably will get hot flashes for the majority of your remaining life.
They should be nowhere near as bad as they were in 2004. I would seek medical advice from your GP or better- the surgeon who carried out the procedure.
Is there a reason you are not taking the hormone replacements?
Regarding weight gain, most women will experience gaining some weight- usually no more than around 5-8lbs. If you have become seriously over weight- you should also consult a professional medical opinion.