Pretty bad unfortunately. I'd recommend you take a slower taper personally. You wanna drop by 1/3 of your current dose every 3 days so from 150mg drop to 100mg a day for 3 days, then 66mg (or as close to 66mg as you can with the pills you have available) for 3 days, then 40mg for 3 days, then 15mg for days, 10mg for 3 days, 5 mg for 3 days then stop.
You're gonna feel like shit, believe me. Ppl compare it to the flu, which is a fair comparison but I'd take flu over Opiate WD any day. Your gonna have really severe pain all over your body, you'll ache from head to toe, ache to move, ache to lay down, ache doing anything. Many people get diarrhea, or at least some very loose bowels, vomiting is common also. You won't be able to sleep for a few days, maybe a week. You'll get 30min sleeps here and there, but nothing longer. I get this next one really bad, and its often the killer than makes me grab a bottle of pills to ease it. its called restless legs syndrome and it may not sound bad but believe me, its the worst of the lot. Its really hard to describe, but if you've ever seen in a film a guy detoxing thrashing around in their bed, that's the RLS. Its a wierd sensation that you get, usually, in your legs. Its fine when your walking, but laying down is impossible because when you stop moving them it kicks in. Its like someone is tickling your nerves, sticking pins right into your muscles. You'll thrash about, constantly have to move your legs to ease the RLS. It'll stop you sleeping. You'll be so tired and just wanna lay down but the sleep won't come, and you'll basrely be able to lay down comfortably. You won't be able to stand comfortably either. In fact you won't be comfortable doing anything for the first 5 days. Your nose may run alot too, and I get runny eyes, looks like I'm crying. Cold sweats are a bitch too. Your freezing cold but you're sweating like you just ran a marathon across the Nevada desert, then you put your sheet over you, even though it hurts to have it touch your skin. A few minutes later your boiling hot and sweating morel, but taking the sheet off only brings back the chills. The finally thing that I know of, which is rather embarrassing and only happened to me once, is spontaneous ejaculations. I went to the toilet, shook my piece clean, and busted a load at the same time! Freaked me the fuck out lol don't hear about this much, though it is embarrassing so maybe ppl just don't mention it. This may happen though so don't be shocked if it does.
So here's what you wanna do to get through this:
If your gonna drop quickly, you want to get some supplies in to help the WD. Get loads of Loperamide, its an anti-diarrhea med and also an opiate that doesn't cross into your nervous system so you don't get high, but it helps with other stuff like the shits, nausea, aches to some degree etc.
Then you'll want Paracetamol (Acetaminophen), an anti-inflammatory like Ibuprofen (Advil), Naproxen (Alleve I think), some heat rubs etc. for aches. If you can, get a tens machine. It sends small electrical shocks to your muscles and causes them to release endorphins (exactly what you want since endorphins are the bodies Opiates and stop being released when you're addicted to Opiates. Your WD won't stop till you've got your endorphins back so the tens machine will help in that respect)
A drug called Clonidine is often used for WD. It blocks the release of epinephrine so helps treat the lack of sleep, sweats, irritability and anxiety.
If you can get it, I swear by a drug called Pregabalin (Lyrica). If you can get it it works wonders for WD. Start taking 75mg twice a day before you quit, then increase to 150mg twice a day after 3 days and 300mg twice a day after another 3 days. If your ready to quit now you might as well go straight for the 300mg twice a day. It'll make you feel a bit spaced and dizzy, a little drunk maybe, but that's a hell of alot better than WD.
Hot baths are the savior of the detoxing addict. They ease all the aches and relax you. Whilst its hot, for me anyway, all my symptoms dissipated. Though be careful if your suffering the shits bad as that'd make things even worst if you shat in your own bath water lol When you get out the bath they all come back unfortunately, but whilst the bath is hot, it gives you half an hour or so of relief which you'll appreciate so much. You could really get out and run another hot bath if you wanted, spend the whole WD in the tub. Whatever helps I suppose.
Try to eat if you can, and drink LOTS of fluids to replace all the fluid lost from shits and vomiting. Even if you throw it straight back up, just keep drinking.
Weed also helps. It treats nausea, is a great pain reliever and relaxes you. It may aid sleep too, but I'd say avoid Benzos if you can, as its easy to get addicted to them in the process. If you will use them, take them for the first 5 days only then stop. Make sure you start with a safe dose, and increase by 50% of that dose at a time til you got the right dose. Wait an hour before you re-dose so the previous dose can kick in.
Good luck with your kick. Its not gonna be easy, and if you can get through it, you earn the ability to approach any tough task in your life and know that if you can beat Opiate WD, you can do this no problem. It puts things in comparison. I hope you can do it, but if you can't, don't worry,alot of ppl fair to get through it. But you can always try again when your ready, or do a slower tapper. Whatever happens, keep trying to quit. One time you'll manage it, whether it be this time or the next or the tenth time. You WILL do it if you keep trying.