he likened the withdrawal symptoms to have a flu for 3 days; and said the whole opiate withdrawal being terribly difficult was just BS
He clearly has never gone through a hardcore heroin withdrawal, or methadone withdrawal. While it won't KILL you, it certainly is much fucking worse (for me at least) than any flu I have had. I survived cancer and chemo therapy and whatnot and JUST finished over a year of straight treatment, and I would rather repeat that year, than endure dope withdrawal cold turkey again.
Anyways, you seem to have tapered, albeit quite fast, and haven't been using for very long so while it will definitely be uncomfortable, I think your detox should be bearable with the help of a few comfort meds. Loperamide is a godsend, benzos if you have access, plenty of fluids, exercise, things to occupy your mind, vitamins, a muscle relaxer.
There are a billion threads on withdrawal, use the search engine and you will find a plethora and a half of info to help you.
Nevertheless, I wish you luck, you'll be ok !