Melatonin can sure help, but when it comes to acute opioid w/d it's not all that effective. I think we can pretty much all agree that the less medication necessary, the better. Anyone can detox of an opioid (more or less) without any meds, but there's no reason to suffer needlessly. I guess it's good to experience discomfort in withdrawal, as a kinda deterent force, but I don't think masochism is very useful. Balance, as in everything
And while meds can be important and very valuable, I think what we do outside taking meds while detoxing is even more important. I.e. exercise, healthy diet, sleep, avoiding too much stress, being good to yourself, doing things you love, etc.
I've tried a number of ginger products in opioid withdrawal, cause I love ginger and generally find it very effective at combating nausea. But honestly, in acute withdrawal, if I'm feeling nauseous, ginger anything just is not going to do it. Even cannabis won't really solve the problem, although it can help. Only thing that works for me (granted, I've crohns disease) is Zofran. The Zofran should make a big difference with the nausea! I'm stoked to hear you have some available. I find it take a little while to kick in, and it doesn't really solve the lack of appetite issue, but it does make a big difference in terms of making is actually possible to swallow!
I wouldn't worry too much about developing a pregabalin habit. I mean, it is a concern, absolutely, but the majority of people can have a month of pretty damn regularly pregabalin use and walk away pretty unscathed. It's great that is avaliable. The gabapentin is also good to have. It obviously isn't as useful as the pregabalin, and requires much higher doses to be as effective (as in like 4g doses vs 600-900mg). Gabapentin can also create dependency, so in that regard it isn't a god send. Probably lower potential for it than pregabalin given potency, but it's possible for both. In your case I wouldn't worry about this though.
If you're that uncomfortable, I'd totally take as much pregabalin as necessary, safely of course. Go get a message every day or every other day, at least when you're feeling especially shitty. That makes a huge difference. And jacuzzis/saunas are amazing. Manicures can also be awesome, anything that makes you feel good about yourself and how you look. Look good, feel good, right?
And I also agree with CJ again, day 10 of a methadone detox isn't nearly over the hump. It's more like you now know what the hump is. I doubt it would get much if any worse though. The worst thing about methadone detox is the insomnia IME. It tends to go on and on, which is why I begin to obsess over healthy ways to get some sleep pretty early on in the process (exercise, massage, medication, low sugar, no caffeine, etc. etc.).