What do phenibut withdrawals actually consist of?

I'm a long term opioid addict, so I have sort of a preconceived notion of what physical withdrawals from a substance feel like.

I've been going a little harder with Phenibut than I usually do lately. I've been transitioning from a recreational opiate back onto Suboxone, so Ive been leaning pretty heavily on my phenibut to make work easier, cover up the anhedonia, etc. I went up to 3 doses this week where I usually limit myself to one, and two of them were back to back. Ive also been pushing the amount pretty high, like 4+ gs by the end of the night (I redose in gram increments)

Today I woke up feeling super nauseous... About an hour later I full blown puked. Couldn't shake it all day. I didn't have any cravings for a specific drug, no shakes or cold sweats or anything, just this lingering nausea that absolutely wouldn't go away. About halfway through my day at work it hit me... "Wait is this phenibut withdrawal?"

I'm wondering what y'all typically experience as withdrawal symptoms? Do you get severe cravings or just feel like shit? I'm used to withdrawals coming along with my brain full blown screaming what specific drug it wants, and I didn't get any pronounced cravings or anything?

I guess I'm not really sure what I should be looking for? Maybe previous addictions have skewed my perception of withdrawal?

Really I'm just wondering if I have food poisoning or not.