I stopped taking buprenorphine a week ago 1mg/day been taking it for 6 yrs. i have insomnia, pain & nausea. how long will my withdrawals last?

Try a slower taper: I tell my patients to go down to 1/2 mg a day for a while before they stop completely. After that, symptoms are less severe, more tolerable and when they eventually stop altogether it can take 2-4 weeks for the withdrawals to stop completely, but they are milder and more tolerable. A lot depends upon how long you've been on it of course.

Few weeks: It sounds like you might have some withdrawal symptoms. The symptoms should continue to improve. It might take couple more weeks until you feel completely better. Hang in there.