I am going to say things that you might not like- warning :)
I am not a great fan of expensive products that are advertised as wonder treatments!
No product IMO not even traditional HRT will stop symptoms over night. In the peri phase your hormones are all over the shop- you can have flushes etc that come and go overnight for months. Some women don't even have any. What is more likely is that you are not yet post meno, you still have some estrogen ( as shown by your period) and it's nothing to do with Amberen.
I've had a look at the Amberen website and it raises lots of questions. If a product could reverse ageing without use of hormones then surely it would be available on the NHS or at least from menopause specialists?
They use a lot of scientific terms which TBH are meaningless to anyone without a degree in chemistry or biochemistry. BUT it's a very clever and cynical marketing ploy because it implies the products work.
They say they have done double blind trials but they don't publish any results such as whether the researchers are independent, or how many women were in the trials- this is crucial to all research as small numbers of subjects ( fewer than thousands) are meaningless.
The other point is that if Amberen was able to turn back the clock and put your hormones back to where they were, it would be a potentially dangerous supplement, with side effects potentially the same as HRT can be for some women.
The other point is that if you are over 50 now ( are you?) and have had a period after a 14 month gap, you ought to see your GP as this is classed as post menopausal bleeding and should be investigated. The usual advice is any bleeding 12 months after a 'final' period needs investigating.
Sorry if this sounds a bit negative- but best talk to your dr.